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Acknowledgements
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Lyndersay
Digital,
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at
Contents
Introduction
Section
Unit
1
A:
Principles
States
of
1.1
The
1.2
Diffusion
1.3
Changing
Unit
2
1
three
of
Mixtures
Elements
Pure
2.3
Solutions,
2.4
How
2.5
Filtration,
of
matter
7.1
Acids
7.2
Acidity
7.3
The
2
and
and
compounds
substances
and
suspensions
solubility
and
changes
2.7
Chromatography
colloids
3.2
Protons,
3.3
Isotopes
Unit
4
The
Uses
Solubility
7.6
Acid–base
7.7
Neutralisation,
of
acids
10
salt
64
preparation
66
salts
68
and
solution
concentration
7.8
Solution
70
concentration
and
titrations
72
12
Unit
and
8
Oxidation
8.1
Oxidation
8.2
Oxidising
8.3
Using
and
and
and
reduction
reactions
reduction
reducing
oxidising
and
74
agents
reducing
agents
76
78
18
and
use
of
9
Electrochemistry
a
funnel
20
9.1
Conductors
9.2
Electrolysis
9.3
The
and
insulators
80
82
structure
structure
of
atoms
neutrons
periodic
periodic
and
table
22
electrons
and
electrochemical
84
of
86
24
9.4
Examples
26
9.5
Electrolysis
9.6
Applications
calculations
28
Unit
10
Rates
of
Group
II
30
10.1
Following
in
Group
VII
32
10.2
Determining
4.4
Periodic
34
10.3
How
trends
area
5.1
Ionic
5.2
Covalent
bonding
36
5.3
Ions,
molecules
5.4
Ionic
compounds:
bonding
and
molecular
molecular
formula
structure
and
units
40
and
Unit
11
11.1
giant
structures
structures
of
rates
of
of
a
reaction
reaction
and
92
94
surface
reaction
How
temperature
rates
of
and
96
catalysts
reaction
98
44
Energetics
Exothermic
and
endothermic
changes
100
11.2
Energy
11.3
Calculating
46
changes
Summary
by
energy
experiment
changes
questions
exam
102
104
106
questions
108
concept
6.1
Moles
and
6.2
Balancing
6.3
Mole
calculations
(1)
52
6.4
Mole
calculations
(2)
54
Summary
course
rates
concentration
Practice
mole
the
affect
affect
42
Comparing
90
38
properties
5.6
electrolysis
bonding
10.4
Simple
of
88
reaction
in
5.5
electrolysis
periodicity
table
and
and
products
Trends
Structure
series
electrode
Trends
The
carbonates
and
titrations
4.3
6
and
rules
4.2
Unit
acids
62
The
5
60
some
bases
4.1
Unit
of
7.5
with
sucrose
separating
reactions
and
Unit
The
58
alkalinity
7.4
16
Extracting
3.1
salts
bases
and
6
14
crystallisation
2.6
Atomic
and
and
4
8
mixtures
distillation
3
bases
separations
temperature
Unit
Acids,
chemistry
states
2.2
7
matter
states
2.1
Unit
molar
masses
equations
questions
48
50
Section
Unit
12
B:
Organic
Organic
chemistry
chemistry:
12.1
Organic
12.2
Homologous
an
introduction
structures
series:
110
formulae
56
and
nomenclature
12.3
Isomers
and
12.4
Sources
of
their
nomenclature
hydrocarbons
112
114
116
iii
Contents
Unit
13
Reactions
of
carbon
compounds
Unit
16
Non-metals
13.1
Alkanes
118
16.1
Properties
13.2
Alkenes
120
16.2
The
13.3
Alcohols
122
16.3
Uses
13.4
Fermentation
124
13.5
Alkanoic
126
13.6
Esters
Unit
14
Large
acids
14.1
Soaps
14.2
Polymers
14.3
Condensation
Practice
exam
molecules
16.4
Unit
15
C:
Inorganic
Properties
15.2
Reactions
of
Leaching,
136
Metals
and
metals
of
non-metal
156
of
water
hard
158
water
18
Green
160
chemistry
18.1
The
18.2
Examples
some
principles
of
of
green
green
iv
Metals
162
164
19
Qualitative
analysis
metal
19.1
Identification
of
cations
166
19.2
Identification
of
anions
168
19.3
Identification
of
gases
170
140
the
electrochemical
of
iron
and
aluminium
exam
questions
metals
and
alloys
and
the
environment
172
144
174
146
Periodic
15.6
chemistry
chemistry
Glossary
of
water
142
Extraction
Uses
and
treatment
Practice
15.5
their
138
series
15.4
and
chemistry
compounds
15.3
152
Water
17.2
Unit
of
17
132
questions
150
gases
154
effects
Properties
Metals
15.1
Harmful
17.1
134
non-metals
non-metals
130
Unit
Section
of
of
compounds
Unit
polymers
some
compounds
128
organic
of
preparation
table
180
148
Index
181
Acknowledgements
188
Introduction
This
Study
Guide
has
been
developed
exclusively

On
Your
Marks
activities
provide
sample
®
with
be
the
used
both
in
Caribbean
as
an
and
Examinations
additional
out
of
Council
resource
school,
by
following
(CXC
)
to
examination-style
candidates,
example
the
an
examiner
be
improved.
Caribbean
short
candidate
to
answer
answers
show
questions,
and
where
feedback
answers
with
from
could
®
Secondary
Education
Certificate
(CSEC
)
programme.
These
understanding,
It
has
been
prepared
by
a
team
with
expertise
skill
activities
level
will
and
build
your
confidence
in
in
answering
examination
questions.
®
the
The
CSEC
syllabus,
contents
providing
are
tools
teaching
designed
to
help
and
to
you
examination.
support
achieve
learning
your
best
by
in
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it
Chemistry
easier
for
you
requirements
to
your
requirements
Inside
this
to
of
syllabus
and
the
Study
features
master
for
and
the
the
syllabus.
full
key
Do
guidance
examination
Guide
is
an
included
make
concepts
and
remember
on
the
to
refer

T
est
Yourself
provide
questions
sections
revise
activities
experience
and
inside
of
helpful
the
problem
are
specifically
multiple-choice
feedback
Study
Guide
will
so
designed
to
examination
refer
that
you
you
to
can
areas.
course
This
unique
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of
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syllabus
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format!
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full
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developing
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to
examination
assist
you
in
potential
in
CSEC
Chemistry.
techniques:
1
1
States
of
1.1
matter
The
of
the
end
liquids
of
this
topic
be
able
three
states
describe
of
the
matter
in
three

explain
liquids
the
DID
the
YOU
gases
are
so
in
a
of
in
solid

liquid

gas
of
atoms
pinhead,
that
of
millions
T
o
the
you

All

The

of
line
matter
y
of
the
are
ano th
er
.
you
them
gases.
on
Most
the
temperature.
between
0 ºC
and
100 ºC
100 ºC.
theory
of
matter
The
width
would
is
made
liquids
are
either
and
forces
particles
up
that
of
particles.
vibrate
(as
in
solids)
or
move
from
place
to
place
gases).
of
attraction
make
up
and
matter
repulsion
can
be
between
atoms,
the
particles.
molecules
or
ions.
of
An
atom
is
the
smallest
particle
that
cannot
be
broken
down
by
a
means.
need
atoms.

A
molecule
An
be
the
ion
is
is
a
particle
same
an
or
atom
containing
two
or
more
atoms.
The
atoms
different.
or
group
of
atoms
with
either
a
positive
or
charge.
TIP
liqui
d
each
and
depending
0 ºC
above
particles
in
There
We
that
below
(water)
negative
one
liquids
states
up

a
solids,
is
particulate
can
Man
water
(steam)
The
there
10 000 000 000 000 000
EXAM
are
three
matter
.
(as
pinhead.
(ice)
chemical
large
all
solids,

hydrogen
in
and
terms
theory
small
and
example,

KNOW?
millions
them
motion
nature
and
matter
of
particles
particulate
Atoms
are
of
of
exist
states
terms
arrangement,
proximity
can
to:
For

gases
you
substances
should
and
OUTCOMES
The
At
states
matter
Solids,
LEARNING
three
parti
explain
the
nature
of
solids,
liquids
and
gases
by
looking
at:
in

how
the
particles

how
close

the
motion

the
strength
are
arranged
touchi
ng
Mak
e
don’
t
well
cles
can
the
particles
are
to
each
other
sure
of
the
particles
draw
separa
ted
of
the
attractive
forces
between
the
particles.
from
o ther
.
(See
Figures
1.1.1–3.)
Solids
Arrangement
Closeness
of
of
particles:
particles:
regular
very
close
pattern
or
touching
each
other
Strong
attractive
Motion
of
particles:
vibrate
around
a
fixed
point
but
do
not
forces
from
Figure
1.1.1
Particles
in
a
solid
place
Attractive
to
place
forces
between
the
particles
are
strong.
Liquids
Weak
forces
Arrangement
Closeness
Figure
1.1.2
Particles
in
a
particles:
particles:
irregular
very
close
or
–
no
particular
touching
each
pattern
other
liquid
Motion
2
of
of
of
particles:
move
(slide)
over
each
other
slowly
move
Attractive
stronger
forces
than
between
in
the
particles
are
weaker
than
in
solids
but
gases.
Gases
Arrangement
Closeness
Motion
There
of
of
are
of
particles:
particles:
particles:
almost
Explaining
far
irregular
apart
move
no
the
pattern
everywhere
attractive
forces
nature
of
Figure
1.1.3
Particles
Figure
1.1.4
Solid
Figure
1.1.5
Liquid
Figure
1.1.6
Gas
in
a
gas
rapidly
between
solids,
the
particles.
liquids
and
gases
Solids
Solids
have
(squashed
This
the
is
a
definite
shape
together).
because
particles
the
close
They
strong
or
and
do
volume
not
flow
attractive
touching
each
and
like
cannot
liquids
forces
be
(see
between
compressed
Figure
the
1.1.4).
particles
keep
other.
Liquids
Liquids
and
the
have
they
shape
of
attraction
have
definite
flow
the
volume
(see
Figure
container
between
enough
compressed
close
a
can
the
energy
in
but
which
particles
to
slide
(squashed)
very
they
1.1.5).
are
over
not
not
this
they
each
easily.
do
For
are
very
is
a
placed.
so
Liquids
because
definite
they
The
strong,
other.
This
have
reason,
can
forces
the
of
particles
cannot
the
shape
take
be
particles
are
together.
Gases
Gases
do
not
everywhere
forces
of
KEY
(Figure
with
the
The
2
In
three
solids
of
states
the
This
are
far
is
the
solids
In
the
liquids
In
gases
move
Solids
Solids
can
only
or
or
volume.
because
there
particles.
liquids.
They
Their
They
are
can
hardly
density
can
spread
be
is
any
very
low
compressed
apart.
slide
a
on
the
liquids
and
gases.
arranged
and
close
spot.
irregularly
each
are
solids,
arranged
and
close
other.
irregularly
arranged
and
far
apart,
everywhere.
gases
liquids
are
regularly
are
over
definite
and
and
are
vibrate
particles
rapidly
have
matter
particles
and
the
of
particles
and
container
6
shape
between
that
together,
and
5
1.1.6).
particles
together,
4
definite
POINTS
1
3
a
attraction
compared
because
have
shape,
spread
cannot
liquids
take
the
shape
of
their
everywhere.
be
compressed
easily,
but
gases
be.
3
1.2
Diffusion
Diffusion
LEARNING
OUTCOMES
In
At
the
end
should

explain
and

be
of
this
able
the
topic
terms
how
and
movement
particles
in
colliding
diffusion
called
evidence
liquids
with
the
on
osmosis
is
supports
due
describe
as
In
the
to
diffusion
why
salt
or
sugar
preservatives
garden
and
are
define
gases
The
are
idea
particle
spreading
aske
d
Diffusion
crystal
in
in
overall
gases
gases
of
of
constantly
that
changing
particles
are
movement
of
movement
one
of
in
direction
constant
substance
the
an
the
of
gradually
it
direction
of
movement
to
where
is
they
from
are
the
concentrated.
is
faster
move
than
faster
in
liquids.
than
those
This
in
is
because
the
liquids.
diffusion
manganate( VII)
in
water
potassium
rather
of
to
is
manganate( VII)
placed
in
water.
(also
The
called
colour
of
potassium
the
manganate( VII)
spreads
out
through
the
water
until
there
is
the
overa
ll
of
colour
throughout
(Figure
1.2.1).
This
is
because
particles
and
the
water
particles
in
from
of
parti
cles
is
than
motion,
bumping
into
and
bouncing
off
each
o ppos
ite
the
other.
the
At
start
After
Alth
ough
of
particles
Manganate(VII)
particles
parti
cles
their
is
low,
high
Cr ystal
of
potassium
manganate( VII)
some
Figure
are
the
in
low
where
it
are
or
parti
cles
conc
entra
tion
where
both
solution
of
direc
tion
movem
ent
same
is
constant
movem
ent
high
becaus
e
through
where
less
Water
the
movin
g
1.2.1
After
in
of
the
the
crystal
of
potassium
manganate( VII)
manganate(
gradually
spreads
VII)
has
dissolved,
throughout
the
the
colour
water.
direc
tion
movem
ent
is
Diffusion
of
gases
rand
om .
Hydrogen
up

as
The
chloride
shown

in
After
a
and
Figure
hydrochloric
aqueous
acid
ammonia
few
ammonia
gives
gives
minutes
are
gases.
A

The
ring
is
nearer
long
glass
tube
is
1.2.2.
a
off
off
white
hydrogen
ammonia
ring
is
chloride
the
hydrochloric
gas
and
the
gas.
seen
nearer
tube.
4
is
answ
er
sprea
ding
conc
entra
tion.
to
and
motion
particles.
concentrated
potassium
manganate(VII)
parti
cles
is
The
to
depth
give
movem
ent
the
movement.
direction.
theory.
random
more
permanganate)
diffus
ion,
to
rand
om
from
any
pests.
A
abou
t
random
in
TIP
you
be tte
r
go
are
Diffusion
If
constant
to
Examples
EXAM
and
the
the
are
particles
control
in
particles
the

used
are
the
theory
particles

that
from

particulate
particles
diffusion
another
and
the
means
others.
kinetic
Diffusion
experiments
gases,
Random
to:
osmosis
explain
liquids
you
acid
end.
one
end
of
the
set
We
can
explain
this
using
the
particle
model.
Cotton
in

The
hydrogen
constant

They
the
chloride
and
ammonia
particles
(molecules)
are
wool
soaked
Cotton
ammonia
in
acid
motion.
bump
into
and
bounce
off
air
molecules
and
so
move
along
tube.
The
white
ring
is
formed
where
the
reacted
to
hydrogen
chloride
have
met
and
form
a
white
ring
1.2.2
Reaction
white
ring
is
nearer
hydrogen
chloride
molecule.
Heavier
is
a
the
hydrochloric
heavier
molecule
acid
end
than
an
move
more
slowly
hydrogen
and
ammonia
because
ammonia
DID
molecules
of
solid.
chloride
The
forms
and
Figure
ammonia

soaked
in
White

wool
hydrochloric
than
lighter
YOU
KNOW?
ones.
Salts
such
as
(magnesium
Epsom
salts
sulfate)
can
be
Osmosis
Osmosis
is
a
movement
of
membrane
where
it
is
special
water
from
at
case
a
of
diffusion.
molecules
where
lower
the
Osmosis
through
water
is
at
a
a
is
the
selectively
higher
overall
permeable
concentration
used
to
control
such
as
slugs
The
to
concentration.
on
can
be
demonstrated
using
thin
strips
of
pawpaw
fruit
is
the
leaves.
plants
on
distilled
Slugs
because
of
water
the
fruit
or
sugar
can
be
solution
thought
of
(Figure
as
1.2.3).
being
a
The
contents
solution
of
in
water
.
The
cell
membrane
is
selectively
of
of
the
properties
the
the
salt.
Some
sodium
gardeners
chloride
for
this
permeable.
purpose
Strip
avoid
of
different
use
substances
or
placed
of
cells
the
plants
water-withdrawing
in
pests
beetles.
sprayed
around
the
the
Osmosis
salt
earth
garden
and
but
this
‘leaf
burn’.
KEY
POINTS
may
cause
pawpaw
Cell
in
pawpaw
In
distilled
In
water
sugar
solution
a
b
Water
in
Figure
Water
1.2.3
Strips
b
of
sugar
pawpaw
fruit
are
placed
in
a
distilled
out
water,
solution.
1
Diffusion
is
movement
In
distilled
water
the
strips
become
longer
and
more
rigid.
This
the
of
spreading
one
substance
is
through
another
due
to
the
because:
random

the
water

water
outside
passes
the
into
cells
the
is
cells
more
by
concentrated
than
inside
the
2
Osmosis
of
In
sugar
solution
the
strips
become
shorter
and
softer
The
water
outside
the
cells
is
less
concentrated
than
water
is
the
cells.
This
is
because
there
is
sugar
as
well
as
the
water
water
Water
passes
out
of
the
cells
by
in
the
uses
of
sugar
and
osmosis.
fungi
or
from
survival.
water
salt
are
growing.
Foods
from
used
with
bacteria
to
The
a
or
is
at
a
lower
a
where
to
higher
where
it
is
concentration.
salt
preserve
cells
high
water
concentration
3
Sugar
from
solution.
at
Some
through
permeable
inside
the

movement
molecules
selectively
membrane
the
the
(flaccid).
a

of
particles.
cells
osmosis.
movement
of
food.
all
They
organisms
concentration
fungi
by
stop
osmosis,
of
so
bacteria
depend
sugar
they
or
on
salt
and
water
Results
on
for
remove
from
diffusion
experiments
and
provide
evidence
particle
theory.
osmosis
for
the
die.
5
1.3
Changing
Changes
LEARNING
the
end
of
this
topic
be
able
we
liquid
explain
the
melting,
terms
boiling,
condensing

and
curves
terms
the
freezing,
special

T
he
and
of
turns
below
its
point.
in
liquid.
gas
Further
turns
heating
into
a
turns
liquid.
Further
liquid
into
a
solid.
These
changes
of
state
are
given

Melting:
solid
→
liquid

Boiling/evaporation:

Condensing:

Freezing:
→
liquid
gas
gas
→
liquid
liquid
and
→
solid
changes

In
melting
and

In
condensing
of
state
boiling/evaporation,
energy
is
absorbed
(taken
in).
the
(See
Figure
and
freezing,
can
released
(given
out).
1.3.1.)
Energy
taken
in
happ
en
and
occurs
liqui
d
bo th
are
GAS
SOLID
LIQUID
who le
balanc
e
is
Evap
oration
boiling
liqui
d
energy
have
Boili
ng
bubb
les
and
the
differe
nt
liqui
d
when
a
the
forces
‘evap
oration
’
‘boili
ng’
meani
ngs.
a
into
cooling,
TIPS
sligh
tly
of
turns
cooling
particles.
term
s
and
it
On
names.
Energy
EXAM
solid
gas.
evaporation,
heating
between
a
a
sublimation
interpret
in
into
to:
cooling

heat
you
the
should
state
OUTCOMES
When
At
of
states
gas
Energy
given
out
presen
t
Figure
with
1.3.1
Energy
is
required
to
melt
and
boil
a
substance.
Energy
is
released
one
when
a
substance
condenses
or
freezes.
ano th
er
.

We
usua
lly
term
the
of
is
gase
ous
a
use
‘ vapo
ur ’
Heating
fo rm
subs
tanc
e
no rm
ally
the
Figure
that
is
so lid
at
1.3.2
heated
cooling
curves
shows
slowly
to
how
form
the
a
temperature
liquid
and
of
then
a
a
solid
changes
when
it
gas.
liqui
d
We
or
and
fo r
can
explain
the
shape
of
the
curve
using
ideas
of
energy
(heat)
room
transfer
to
the
particles.
tempe
rature.

We
some
times
term
the
1
use
AB:
Increasing
particles
‘ vapo
risat
ion’
chan
ge
liqui
d
in
the
energy
solid.
So
increases
the
the
temperature
vibrations
of
the
of
solid
the
increases.
fo r
→
2
gas.
BC:
The
forces
weakened
The
the
temperature.
3
CD:
of
in
is
so
The
the
that
energy
liquid.
So
the
particles
because
between
substance
the
between
the
constant
forces
Increasing
particles
attraction
enough
temperature
overcome
6
heat
the
the
particles
slide
the
over
energy
particles
are
each
is
instead
other.
going
of
in
to
raising
the
melts.
increases
the
the
movement
temperature
of
the
of
the
liquid
increases.
4
DE:
The
forces
of
attraction
between
the
particles
are
weakened
DID
enough
The
so
that
the
temperature
overcome
the
temperature.
is
particles
constant
forces
The
move
well
because
between
substance
the
away
the
from
energy
particles
is
each
going
instead
of
in
to
EF:
Increasing
So,
the
the
energy
temperature
raising
the
metal
low
melting
change
boils.
increases
the
speed
of
the
gas
KNOW?
The
you
5
YOU
other.
gallium
from
hold
it
has
point
a
in
such
that
solid
your
to
a
it
will
a
liquid
if
hand.
particles.
increases.
) C° (
erutarepmeT
F
Liquid
Gas
up
) C° (
Boiling
heating
vaporising
D
point
E
Solid
B
Melting
heating
erutarepmeT
Liquid
A
up
B
C
melting
point
D
C
Solid
heating
E
up
A
F
0
5
10
15
Time
Figure
1.3.2
A
substance
show
is
where
heated
the
at
a
20
(min)
Time
constant
substance
is
rate.
melting
(B
The
to
flat
C)
parts
and
of
boiling
the
(D
curve
to
Figure
1.3.3
A
a
E).
substance
constant
parts
of
where
Figure
1.3.3
cooled
1
to
When
shows
form
the
a
gas
(movement
how
liquid
is
the
and
cooled,
energy).
The
temperature
then
the
a
of
a
gas
changes
when
it
is
particles
freezing
lose
kinetic
falls
The
particles
3
Energy
become
attracted
to
each
released
and
the
gas
turns
to
When
the
liquid
a
liquid
is
falls
cooled,
the
Energy
is
(D
(B
to
to
C)
is
and
E).
POINTS
Melting
particles
lose
is
more
energy.
→
the
change
liquid.
The
Boiling
is
the
change
(CD).
liquid
5
show
substance
(BC).
2
temperature
curve
at
flat
other.
solid
4
The
energy
1
is
cooled
(AB).
KEY
2
the
the
is
rate.
condensing
solid.
temperature
(min)
released
and
the
liquid
turns
to
a
solid
→
gas.
(DE).
3
Condensing
gas
→
is
the
change
liquid.
Sublimation
4
Sublimation
is
the
direct
change
of
a
solid
to
a
gas
on
Freezing
liquid
without
change
any
of
a
liquid
gas
state
to
a
being
solid
on
formed.
cooling
It
also
without
refers
the
to
the
liquid
is
the
change
heating
→
solid.
direct
state
being
5
Sublimation
solid
formed.
gas
→
→
is
gas
the
change
or
solid.
heat
6
Energy
a
solid
is
absorbed
melts
and
a
when
liquid
cool
changes
For
example,
solid
carbon
dioxide
changes
directly
to
carbon
when
a
gas/vapour.
dioxide
7
gas
to
Energy
is
released
when
a
heated.
gas
condenses
liquid
and
when
a
freezes.
7
2
Mixtures
2.1
and
separations
Elements
and
compounds
Elements
LEARNING
OUTCOMES
An
At
the
end
of
this
topic
element
cannot
should
be
able
explain
the
terms
explain
and
substance
down
made
into
up
of
anything
only
one
simpler
type
by
of
atom.
chemical
Elements
reactions.
examples
different
of
but
elements
each
one
are
of
shown
them
in
Figure
only
has
2.1.1.
one
only
carbon
type
The
of
structures
atom.
Chlorine
compound
has

a
broken
element
look
and
be
to:
Some

is
you
that
only
chlorine
atoms,
carbon
has
atoms
and
so
on.
elements
compounds
are
pure
substances

explain
the
difference
between
physical
chemical
properties.
EXAM
When
is
you
describ
e
mak
e
in
that
an
sure
are
of
answ
er
one
contai
ns
no t
all
that
2.1.1
Each
of
these
four
elements
is
only
made
up
of
one
type
of
atom.
elem
ent
type
only
.
Chemical
such
only
as
one
bonds
‘it
atom
’
co rrec
t.
In
Figure
joined
2.1.1,
by
the
chemical
atoms
A
chemical
bond
is

A
chemical
bond
shows

The
of
chlorine,
phosphorus
and
carbon
are
bonds.

atoms
YOU
Carbon
the
Figure
the
An
DID
Neon
Phosphorus
clear
atom
s
is
Chlorine
TIP
elem
ent,
it
and
shown
by
that
a
line
there
joining
are
the
strong
atoms.
forces
holding
the
together.
bonds
shown
here
are
called
covalent
bonds
(see
5.2).
KNOW?
Compounds
Some
forms
of
chemical
A
elements
are
made
compound
atoms
and
can
few
seconds.
only
exist
for
(or
ions)
rutherfordium-260
than
a
can
only
made
together
by
up
of
two
or
more
different
bonds.
a
have
water
a
fixed
molecule
amount
always
of
has
each
two
element
hydrogen
in
them.
atoms
and
exist
oxygen
atom.
In
sodium
chloride
(salt)
the
ratio
of
sodium
ions
second.
to
chloride
There


are
ions
two
molecular
(see
8
always
example,
one
less
substance
example,
For
for
a
joined
a
Compounds
For
is
artificially
is
always
main
(or
1 : 1
groups
giant
of
(see
Figure
2.1.2).
compounds:
molecular),
where
atoms
are
bonded
together
5.2)
ionic,
where
positive
and
negative
ions
form
‘ionic
bonds’
(see
5.1).
−
−
+
Oxygen
Hydrogen
+
−
+
−
+
−
−
Chloride
+
Sodium
Water
Sodium
chloride
EXAM
Figure
2.1.2
Water
is
chloride
a
is
molecular
an
ionic
compound
compound
of
of
hydrogen
sodium
and
and
oxygen.
chloride
TIP
Sodium
ions.
Rem
embe
r
Physical
and
chemical
there
properties
the
Physical
properties
are
ones
that
do
not
generally
depend
on
are
that
two
parts
defini
tion
of
to
a
the
compo
und:
amount
of
substance
present.
Examples
are:


melting
and
boiling
T
here
type

density
(mass

strength
of
is
more
points
substance
divided
by
volume
of
of
T
he
atom
s
(join
ed)
hardness

electrical
Chemical
with
and
thermal
properties
other
substances.
describe
For
reacts
with
chlorine

Sodium
reacts
with
water
are
made
chlorine
by
the
T
able
how
elements
and
compounds
react
to
to
form
form
sodium
sodium
chloride.
hydroxide
and
hydrogen.
elements
often
from.
and
bond
ed
example:
Sodium
Compounds
are
toge th
er
.
conductivity.

Reacting
one
substance)


than
atom
.
have
We
can
sodium
chemical
2.1.1
very
see
chloride.
reaction
Some
different
this
properties
comparing
Sodium
when
physical
by
chloride
sodium
properties
Sodium
of
burns
is
in
sodium,
from
the
the
elements
of
they
sodium,
compound
chlorine
chlorine
Chlorine
the
properties
formed
gas.
and
sodium
chloride
Sodium
chloride
State
Solid
Gas
Solid
Colour
Silvery
Green
White
883
−35
801
KEY
Boiling
point
(ºC)
1
(g cm
An
element
made
–3
Density
POINTS
)
0.97
at
0.00296
up
is
of
a
substance
only
one
type
of
2.17
atom.
room
temperature
2
T
able
2.1.2
Some
chemical
properties
of
sodium,
chlorine
and
sodium
chloride
A
compound
made
up
different
Sodium
Chlorine
of
is
a
two
atoms
substance
or
more
bonded
Sodium
(joined)
together.
chloride
Reaction
with
oxygen
Burns
a
to
white
form
Does
not
react
Does
not
react
3
Compounds
and
powder
are
Reaction
Reacts
with
an
to
form
Reacts
to
Does
not
alkaline
form
an
acidic
–
just
different
physical
properties
from
those
that
of
react
the
water
have
chemical
elements
they
are
made
dissolves
from.
solution
solution
9
2.2
Pure
and
Pure
LEARNING
the
end
of
this
topic
substance
be
able
and
substance
explain
mixture?
compounds
is
pure,
the
terms
composition
we
are
examples
cannot
of
separate
pure
it
into
substances.
any
other
If
parts
to:
(components)

or
you
a
should
mixtures
OUTCOMES
Elements
At
substances
and
in
fixed
it
–
water
sulfur
variable
by
physical
molecules.
molecules.
The
means.
Pure
Pure
sulfur
composition
water
has
of
only
a
has
one
only
one
component
component
compound
is
fixed
in
(see
it
–
2.1).
composition
A

explain
the
mixture
is
an
components.
between
impure
substance
that
contains
two
or
more
different
differences
compounds
It
consists
of
two
or
more
elements
or
compounds
and
which
are
not
chemically
bonded
together
(see
Figure
2.2.1).
A
mixtures

use
differences
points
to
boiling
describe
differences

in
substances
explain
that
other
pure
mixtures
by
can
filtration
physical
of
because
it
sodium
chloride
contains
two
and
a
for
example,
and
is
a
mixture
water.
means.
2.2.1
atoms
Hydrogen
atoms
a
Oxygen
Water
which
b
A
is
Pure
Pure
or
melting
Impure
boils
boils
exactly
water
100 ºC
point
at
of
and
compound.
two
hydrogen
oxygen
in
and
sharp
water
atmospheric
is
contains
atoms
oxygen
only
for
water
molecules
in
every
oxygen
atom.
have
varying
amounts
can
of
it.
melting
exactly
molecule
molecule
It
hydrogen
comparing
have
of
pure
are
mixture
impure:
substances
a
there
hydrogen
100 °C
salt
be
Figure
at
water,
and
Oxygen
water
in
b
Hydrogen
Pure
(salt)
components:
the
between
impure
separated
solution
boiling
points
0 ºC
and
and
the
points
boiling
boiling
points.
point
is
The
exactly
pressure.
above
If
a
substance
is
impure,
the
impurities
will
affect
its
melting
point
100 °C
and
Figure
boiling
point.
2.2.2

The
boiling
point
substances.
DID
YOU
chloride
KNOW?
(Figure
In
countries
that
have
salt
is
spread
on
to
try
to
stop
ice
causing
melting
lowered
means
by
that
of
water
adding
water
The
at
This
turns
adding
from
a
100 ºC
that
is
dissolved,
substance
is
decreased
other
lot
to
the
of
sodium
about
greater
103 ºC
the
rise
in
point.
melting
salt
Mixtures
some
point
to
of
water
a
makes
it
freeze
at
by
adding
temperatures
impurities.
below
0 ºC.
can
be
separated
by
physical
means
components
of
a
mixture
can
be
separated
by
physical
means
way
as
filtration
or
distillation.
0 ºC.
salt
10
point
by
dissolving
to
such
below
salt
by
is
salt.
only
temperatures
boiling
more
increased
The
The
ice
The
the
is
impure
forming
accidents.
point
2.2.2).
boiling
Adding
and
raises
liquid
the

road
it
a
water
cold
the
winters,
in
of
Making
can
be
separated
by:
For
example,
a
mixture
of
sand
and
1
dissolving
2
filtering
the
the
salt
in
mixture
water
–
the
–
the
sand
sand
does
remains
not
on
the
dissolve
fi lter
EXAM
paper
TIP
and
Rem
embe
r
the
salt
solution
goes
that
through
compo
unds
3
the
water
(Figure
is
evaporated
from
the
salt
solution
to
leave
salt
diffe
rent
have
types
them
,
alwa
ys
Filter
a
pure
has
the
Filter
paper
(residue)
of
atom
s
type.
A
mixt
ure
varyi
ng
type
of
Water
can
the
sand
Salt
2.2.3
Separating
Comparing
2.2.1
salt
chan
ge
becaus
e
the
ratio
(pure
Composition
be
from
is
between
and
a
and
a
mixture
Mixture
fixed
Composition
by
physical
Can
be
is
variable
separated
by
physical
properties
the
are
elements
are
different
from
Physical
which
and
made.
the
properties,
density,
are
substances
e.g.
the
in
colour
average
the
Figure
2.2.4
This
of
waste
mixture
chemical
mixture.
Comparing
a
mixture
of
iron
and
sulfur
with
the
waste
is
a
silvery
metal
compound
heated
Some
of
of
and
iron
together.
the
It
sulfur
and
is
(pure
sulfur.
contains
differences
compound
a
yellow
non-metal.
Iron
T
able
It
is
made
sulfur
between
substance)
the
are
when
atoms
mixture
shown
iron
bonded
(impure
in
T
able
and
to
Pure
substances
2.2.2
Differences
between
iron
sulfide
and
a
atoms.
substance)
2
and
Mixtures
or
2.2.2.
mixture
of
iron
and
sulfur
(mixture)
Iron
sulfide
The
colour
is
a
mixture
of
tiny
The
colour
more
contain
and
silver
and
iron
can
be
The
sulfur
using
The
boiling
is
can
made
separated
from
The
iron
cannot
be
point
a
magnet.
from
dissolved
in
an
Iron
the
sulfur
sulfide
using
does
not
a
of
a
pure
increased
impure
by
if
adding
leaving
the
iron
organic
substance.
The
components
can
be
of
a
mixture
magnet.
dissolve
separated
by
physical
in
but
it
is
not
possible
solvents.
separate
the
different
solid.
atoms
When
heat
is
separated
to
a
not
spots.
be
solvent
are
together.
brown-black.
means,
organic
they
bonded
(compound)
4
sulfur
but
or
sulfur
another
The
only
two
elements
compounds
it
yellow
contain
component.
compound
is
the
mixture
given
is
formed,
no
off.
When
heat
the
is
compound
given
is
reaction
gas
with
added.
The
is
formed
iron)
gas
(by
when
does
an
not
Hydrogen
acid
smell.
when
smells
an
of
in
physical
formed,
a
compound
by
means.
off.
5
Hydrogen
is
the
sulfur
iron
3
Iron
as
from
aluminium.
sulfide
chemically
the
a
and
POINTS
one
the
of
is
sulfide
1
a
water
compound
KEY
are
pond
of
extraction
is
add
mixtures
compound
substance)
separated
you
means
Physical
Iron
you
of
sand
means
iron
each
togeth
er
.
compounds
Differences
Compound
they
atom
have
of
crystals
(filtrate)
from
each
can
num
bers
substa
nces
solution
Salt
Cannot
of
of
and
T
able
same
ratio
Sand
Figure
atom
s
compo
und
funnel
Stir
salt
severa
l
of
2.2.3).
in
Mixture
althou
gh
sulfide
acid
bad
is
gas
is
added.
formed
The
gas
The
is
composition
variable
of
a
but
of
the
compound
is
a
mixture
composition
fixed.
eggs.
11
2.3
Solutions,
and
Solutes,
LEARNING
the
end
of
this
topic
be
you
able
describe
the
different
types
of
solutions

give
examples
types
of
explain
the
of
sugar
sugar
in
water,
dissolves
in
the
sugar
the
water.
disappears
All
parts
to
of
form
the
a
solution
exactly
the
same.
‘Homogeneous’
component
of
component
is
the
solution
called
the
This
means
is
is
an
the
called
example
same
the
of
a
homogeneous
throughout.
solvent
and
The
the
main
minor
solute
different
solution
more
difference
is
a
uniform
mixture
(homogeneous
mixture)
of
two
or
substances.
solutions,
A
suspensions
and
solute
of
particle
sedimentation
is
a
substance
solid,
a
liquid
that
is
dissolved
in
a
solvent.
The
solute
can
colloids
be
terms
solutions
solutions
between
in
shake
The
are
mixture.
A

and
to:
formed

solvents
you
solution.
should
colloids
OUTCOMES
When
At
suspensions
and
a
or
a
gas.
size,
A
light
solvent
be
scattering.
a
is
solid,
a
substance
liquid
or
that
dissolves
a
solute.
The
solvent
can
also
gas.
Solutions
In
DID
YOU
KNOW?

solutions:
The
particles
than
A
heterogeneous
mixture
is
1
are
so
nanometre
small
in
that
they
diameter.
(1
cannot
be
seen.
nanometre
=
1
They
are
millionth
less
of
a
one
millimetre.)
in
which
uniform
the
Examples
mixtures
chalk
e.g.
composition
(the
of
suspensions,
in
or
is
not
throughout.

water
,
and
They
e.g.
colloids,

The
out
YOU
Colloids
by
are
not
evenly
letting
the
a
be
Light
solution
of
separated
mixture
stand
can
a
by
for
be
solid
transmitted
in
another
filtration,
a
and
through
solid.
do
not
separate
while.
2.3.1
Types
of
solution
Solute
Solvent
Example
Solid
Liquid
Seawater
Solid
Solid
Bronze
Gas
Liquid
Carbonated
(salt
dissolved
in
water)
because
Mayonnaise
(tin
dissolved
in
copper)
heterogeneous
always
of
cannot
is
fog.
the
is
particles
a
the
water
(carbon
dioxide
dissolved
in
water)
distributed
throughout
mixture
transparent.
exception
KNOW?
are
mixtures
generally
The
particles
T
able
DID
are
them.
heterogeneous
are
dust
mist
same)
mixture.
Liquid
Liquid
Rum
Gas
Gas
Air
(ethanol
dissolved
in
a
mixture
of
liquids)
heterogeneous
vinegar
and
oil
(mixture
of
nitrogen,
oxygen
and
other
but
gases)
it
usually
it
to
has
make
does
not
egg
sure
yolk
that
separate
added
the
back
to
colloid
into
Suspensions
separate
layers
of
vinegar
and
oil.
When
milky.
you
The
shake
clay
suspension
water
for
container.
12
a
particles
of
clay
little
The
powdered
in
while,
settling
can
clay
just
water.
the
of
water,
about
When
clay
the
with
be
you
particles
solid
is
the
seen.
leave
settle
called
mixture
We
the
to
call
appears
this
mixture
the
a
of
bottom
sedimentation
clay
of
in
the
A
suspension
is
a
mixture
of
small
particles
dispersed
the
small
particles
settle
in
another
a
substance,
and
in
which
on
standing.
Solution
In
suspensions:
Light

The
particles
1000

They
are
large
nanometres
are
opaque
in
enough
to
be
just
visible.
They
are
more
beam
than
diameter.
(not
transparent)
to
light.
Light
is
scattered
by
b
them
(see
Figure
2.3.1).
Suspension
or

The
particles
can
sedimentation
container
in
–
be
separated
they
which
by
eventually
they
are
filtration.
settle
to
The
the
particles
bottom
of
colloid
undergo
Light
the
beam
placed.
Colloids
Figure
2.3.1
a
Light
is
through
Colloids
have
some
of
the
properties
of
solutions
but
are
more
b
suspensions
in
many
ways.
They
consist
of
one
type
of
particle
Light
or
gas)
dispersed
throughout
another
.
An
example
is
particles
of
vinegar
are
dispersed
in
vegetable
oil
particles
(see
Figure
2.3.2).
suspension
The
light
directly
In

solution.
scattered
by
present
the
in
mayonnaise,
a
where
is
(solid,
small
liquid
transmitted
a
like
is
to
or
not
the
a
colloid.
transmitted
observer.
colloids:
The
particles
than
are
those
are
in
between
a
1
not
large
solution
and
enough
but
1000
to
smaller
be
visible.
than
nanometres
in
those
They
in
a
are
larger
suspension,
so
Vinegar
diameter.
Oil

They
are
them
opaque
(see
Figure

The
particles
are

The
particles
do
(not
transparent)
to
light.
Light
is
scattered
by
2.3.1).
too
not
small
to
be
undergo
separated
by
sedimentation.
filtration.
They
do
not
settle
on
Figure
2.3.2
standing.
Mayonnaise
of
colloid
emulsion
T
able
2.3.2
Examples
of
spread
of
(see
colloid
T
ype
of
colloid
of
Gas
dispersed
dispersed
Liquid
Solid
KEY
in
dispersed
dispersed
Liquid
trapped
A
solute
2
A
liquid
in
in
liquid
liquid
solid
dissolves
solution
generally
A
by
2.3.2).
are
throughout
the
Example
Aerosol
Smoke
particles
Foam
Whipped
Emulsion
Milk
Sol
Paint
Gel
Jelly
(fat
in
oil.
air
cream
in
water)
and
colloid
in
a
a
the
solvent
particles
that
and
to
form
cannot
the
a
be
solution.
seen.
components
They
cannot
are
be
sedimentation.
suspension
light
A
has
in
transparent
separated
4
gas
in
T
able
POINTS
1
3
in
type
an
vinegar
vegetable
Solid
a
colloids
Droplets
Nature
is
called
has
particles
components
has
solution
particles
and
that
can
can
be
be
intermediate
those
forming
seen.
separated
the
in
size
Suspensions
by
scatter
sedimentation.
between
dispersed
part
those
of
a
Figure
2.3.3
Vinegar
is
a
transparent
suspension.
Colloids
scatter
light
and
the
components
separated
by
light.
so
is
Milk
is
cannot
a
be
solution,
to
colloid,
so
scatters
light
sedimentation.
and
appears
opaque.
13
2.4
How
solubility
changes
with
temperature
Solubility
LEARNING
At
the
end
should
be
OUTCOMES
of
this
able
topic
If
a
is
very
soluble
explain
and

the
terms
saturated
solubility
the
solvent,
solution
describe
how
solubility
changes
with
temperature
depends
use
solubility
curves
problems
involving
and
of
mass
deposited
a
that
particular
solvent.
If
to
answer
solubility
substance,
the
solute
we
say
does
that
not
the
appear
substance
to
dissolve
say
that
the
in
water
but
soluble
insoluble
in
water
but
dissolves
at
constant
that
any
the
more
solute
substance
insoluble
say
the
and
temperature,
solution
solid
is
the
in
a
other
in
solution
excess
solid
of
solute
in
is
insoluble.
Some
solvents.
some
unsaturated.
and
is
solvent.
can
If
For
organic
the
present,
example,
may
sulfur
be
is
solvents.
dissolve
solution
we
Solubility
substances
say
more
solute,
cannot
that
we
dissolve
the
solution
is
saturated.
substance
on
we
both
cooling
The
saturated
in
on
If,

dissolves
to:
in

solvent
you
solubility
a
a
solvent
is
the
number
of
grams
of
solutions.
solute
used.
needed
The
solubility
DID
We
these
a
can
is
solution
always
be
per
100
quoted.
dust
or
more
water
of
than
This
solution
it
sodium
to
the
a
in
dissolves
contains
of
crystal
in
grams
is
of
solvent
because
saturated
Hydrated
crystallisation
gently,
solution
tiny
solute
supersaturated.
heated
This
saturated
of
must
hold
contains
compound
speck
saturated
temperature.
solutions
crystallisation.
than
a
KNOW?
thiosulfate
this
with
solutions
call
form
temperature
varies
YOU
Some
to
more
in
its
structure.
its
own
sodium
thiosulfate
solution.
sodium
in
supersaturated
When
water
of
thiosulfate
water
.
Adding
solution
a
results
Potassium
200
in
the
whole
solution
crystallising.
nitrate
) retaw
The
150
effect
of
temperature
on
solubility
g 001/ g (
Potassium
carbonate
When
we
become
ytilibuloS
100
warm
saturated
unsaturated.
temperature
For
solutions
most
of
solutes
most
in
substances,
water,
the
solubility
solutions
increases
as
increases.
Potassium
chloride
A
solubility
form
a
curve
saturated
shows
solution
the
per
mass
100
of
solute
grams
of
dissolved
solvent
at
to
different
50
temperatures.
The
solubility
curves
for
a
number
of
different
solutes
Sodium
in
water
are
shown
in
Figure
2.4.1.
chloride
From
these
graphs
we
can
see
that:
0
0
20
40
60
80
100

Temperature
At
0 ºC,
potassium
potassium
Figure
2.4.1
Solubility
curves
potassium
for
14
is
the
most
soluble
in
water
and

At
80 ºC,
nitrate
is
potassium
the
least
nitrate
soluble.
is
the
most
soluble
and
sodium
chloride
nitrate,
is
potassium
carbonate,
potassium
chloride
sodium
carbonate
( °C )
chloride
and

the
The
least
soluble.
increase
nitrate.
in
solubility
with
temperature
is
greatest
for
potassium


Sodium
chloride
temperature
is
The
in
or
increase
an
almost
solubility
can
use
only
solubility
straight
Calculations
The
shows
a
very
small
increase
in
solubility
as
the
increased.
using
curve
for
with
temperature
is
usually
a
smooth
curve
line.
solubility
potassium
curves
nitrate
is
shown
in
Figure
2.4.2.
We
300
the
temperature
solution
1
the
At
mass
crystals
to
deduce:
start
to
form
when
a
saturated
deposited
a
nitrate
line
XY
when
does
first
a
form
from
a
saturated
saturated
crystals
140 g
on
as
the
solution
solution
it
is
cooled.
containing
cooled
vertical
is
axis
from
to
join
140 g
80 ºC?
the
curve.
ytilibuloS
Draw
solid
temperature
potassium

which
curve
cooled
of
what
at
this
g 001/ g (

is
from
) retaw

information
250
200
B
C
Y
150
X
100
E
F
50

The
is
line
just
YZ
gives
soluble.
the
So
temperature
70 ºC
is
the
at
which
maximum
potassium
temperature
nitrate
at
D
which
A
0
Z
crystals
2
Calculate
solution
will
start
the
to
mass
when
a
form.
of
0
potassium
saturated
nitrate
solution
of
that
would
potassium
come
nitrate
out
is
20
40
of
cooled
60
Figure
2.4.2
Solubility
80 ºC

At
80 ºC

At
40 ºC

On
to
a
mass
of
170 g
of
65 g
of
of
potassium
nitrate
potassium
nitrate
dissolves
(lines
ABC).
dissolves
(lines
DEF).
EXAM
cooling
that
from
comes
out
80 ºC
of
to
40 ºC
solution
is
the
mass
(170 g
–
of
potassium
65 g)
=
nitrate
a
Fractional
crystallisation
crystallisation
substances
which
have
A
warm
concentrated
A
larger
proportion
out.
The
crystals
solute
still
solubility.
purity.
KEY
1
contain
So
the
Filtration
the
small
is
used
to
with
the
solubility
amount
is
separate
containing
higher
procedure
to
solubilities
solute
you
are
of
separate
the
the
two
solutes
solubility
remains
solute
several
in
is
cooled.
crystallises
solution.
with
times
crystals
temperatures.
from
The
you
best
draw
fit
point
to
the
lines
or
sure
cur ve
do
draw
from
mak
e
and
straig
ht
to
cur ve
cur ve
s
provid
ed,
dissolved
different
lower
the
repeated
at
two
aske
d
so lubi
lity
simila
r
used
different
the
a
be
solution
of
with
can
TIP
105 g.
If
Fractional
for
nitrate
40 ºC.
mass
a
100
( °C )
curve
potassium
from
80
Temperature
no t
data
that
of
draw
from
one
ano th
er
.
higher
to
improve
the
the
solution.
POINTS
The
solubility
of
solute
of
solvent
of
The
solubility
3
The
information
solution
the
is
solute
to
in
form
a
a
solvent
saturated
is
the
number
solution
per
of
grams
100 grams
used.
2
calculate
a
needed
of
most
from
mass
of
substances
solubility
solid
increases
curves
deposited
can
with
be
when
a
temperature
used
to
saturated
cooled.
15
2.5
Filtration,
and
crystallisation
distillation
Filtration
LEARNING
OUTCOMES
Filtration
At
the
end
of
this
topic
Figure
should
be
able
2.5.1).
describe
explain
how
distillation

explain
in
points
and
of
filter
from
a
paper
solution
are
very
or
liquid
small,
so
(see
the
tiny
in
large
solution
to
flow
can
flow
through.
through
They
get
but
the
trapped
particles
on
the
in
filter
the
solid
are
paper.

The
solution

The
solid

The
passing
through
the
filter
paper
is
called
the
filtrate
remaining
on
the
filter
paper
is
called
the
residue
and
solid
is
washed
with
a
suitable
solvent
to
remove
traces
of
solution.
distillation
differences
the
of
Crystallisation
boiling
components.
obtain
Figure
paper
solids
the
and
We
Filter
in
work
size
of
undissolved
spaces
distillation
filtration
fractional
terms
particle
too
filtration,
crystallisation

The
to:
particles

separates
you
(highlighted
crystals
from
a
solution
by
the
following
method
(see
also
2.5.2):
red,
Filter
1
Gently
heat
2
Evaporate
the
the
solution
solvent
in
an
until
a
evaporating
saturated
basin
solution
to
concentrate
it.
(crystallisation
funnel
point)
is
reached.
This
is
reached
when
a
drop
of
the
solution
Residue
forms
3
Leave
4
Filter
crystals
the
off
when
placed
saturated
the
on
solution
crystals
and
dry
to
a
cold
cool
them
tile.
and
form
between
crystals.
filter
papers.
Copper(II) sulfate
Filtrate
solution
Evaporating
basin
Figure
2.5.1
Apparatus
for
filtration
Solution
from
Thermometer
evaporating
basin
Leave
Water
for
a
few
days
out
Cold
Heat
to
tile
crystallise
Condenser
Fractionating
Figure
2.5.2
The
process
of
crystallisation
column
packed
glass
with
Water
in
beads
Simple
distillation
Distillate
Distillation
(ethanol)
Simple
distillation
is
used
to
separate
a
liquid
from
a
solid,
e.g.
to
flask
separate
Ethanol
and
involves
salt
the
and
water
processes
from
of
a
solution
boiling
and
of
sodium
chloride.
condensation.
It
Distillation
works
because
water
the
components
to
be
separated
have
very
different
boiling
points.
Heat
The
Figure
2.5.3
In
fractional
the
components
the
column
rates,
their
at
which
boiling
temperature
16
procedure
for
separating
water
from
salt
by
simple
distillation
distillation
move
point
of
1
Heat
2
The
(see
also
Figure
2.5.3):
the
solution
of
salt
in
water
in
a
distillation
flask.
on
and
the
follows
up
different
depend
as
the
column.
water
than
salt.
boils
first
because
it
has
a
much
lower
boiling
point
is
3
The
steam
goes
into
the
condenser.
DID
4
The
condenser
is
at
a
lower
temperature
than
the
boiling
water,
so
the
water
condenses
here,
and
is
collected
in
a
crystals,
The
salt
higher
remains
boiling
in
the
point
distillation
than
flask
because
it
has
a
the
atoms
or
ions
are
flask.
arranged
5
KNOW?
point
In
of
YOU
much
regularly
structure.
water.
In
molecules
some
form
structure.
This
a
is
in
a
lattice
crystals,
part
of
called
water
the
water
of
crystallisation.
Thermometer
Water
Distillation
out
flask
Condenser
Salty
water
Water
in
Distillate
Wooden
Heat
(pure
block
water)
A
Figure
2.5.4
A
Fractional
Fractional
different
used
to
from


a
The
distillation
boiling
points
separate
more
lower
the
vapour
is
of
water
boiling
a
apparatus
used
to
separate
water
from
dissolved
salt
of
in
(see
the
first,
the
or
more
liquids
2.5.5).
This
and
purify
12.4)
liquid
so
as
more
temperature
the
two
(Figure
to
with
method
is
alcohol
alcohol.
boil
more
of
at
separate
other
fractions
and
points),
gradient
than
to
each
components
contains
bottom
is
from
petroleum
volatile
the
the
distillation
distillation
mixture
There
simple
lattice
in
mixture
they
move
volatile
the
(the
up
ones
the
with
column,
component.
column,
which
is
hotter
at
top.
KEY

More
of
the
less
volatile
points)
condense
points,
so
lower
components
down
(the
because
ones
they
with
have
higher
higher
boiling
1
the
more
volatile
components
move
further
POINTS
boiling
up
the
In
filtration,
passes

As
the
mixture
is
heated
more
and
more,
the
vapours
move
up
The
ones
with
lower
boiling
points
move
ahead
of
and
higher
boiling
The
components
of
the
mixture
reach
the
condenser
in
turn.
from
vapour
to
liquid
in
the
condenser
and
the
a
particular
components
of
the
mixture
are
collected
filter
paper.
by
is
heating
carried
a
saturated
and
then
leaving
one
solvent
to
evaporate.
time.
3
The
the
fractions
the
at
on
Crystallisation
solution
containing
filter
residue
They
out
change
the
points.
2

the
those
remains
with
filtrate
through
the
paper
column.
the
column.
boiling
point
and
therefore
the
distance
moved
up
the
Distillation
involving
depends
is
a
process
column
boiling
and
on:
condensing.

the
size
of
the
molecules
–
smaller
molecules
of
similar
types
tend
4
to
have
lower
boiling
points
than
larger
molecules
and
so
The
by
further
up
the
column
than
larger
distillation
the
mass
of
the
molecules
–
lighter
molecules
of
similar
types
differences
have
lower
boiling
points
and
so
move
further
up
the
heavier
in
on
boiling
of
the
components
in
column
the
than
substances
tend
points
to
of
depends
ones
the

separation
move
mixture.
ones.
17
2.6
Extracting
Laboratory
LEARNING
the
end
of
this
topic
be
apparatus
able
new
describe
sucrose
the
extraction
from
sugar
of
however,
cane
cane
in
explain
of
the

the
laboratory
is
often
for
extracting
different
from
compounds
that
used
or
when
the
extracted
the
or
same.
laboratory
made
It
by
is
on
an
difficult
grinding,
to
industrial
extract
filtration
scale.
sugar
and
The
from
principles,
sugar
evaporation
for
the
reasons:
Considerable
vacuum
is
needed
to
extract
the
juice
from
the
fibrous
cane.
crystallisation

centrifugation
in
Ordinary
laboratory
filters
get
blocked
and
it
would
take
too
long
the
to
of
force
treatment
sugar
extraction
the
filtration,
precipitation,
and
in
importance
crushing,
under
is
are
following

used
compounds
to:
compound

extraction
you
making
should
industrial
OUTCOMES
The
At
versus
sucrose
filter
the
sticky
filtrate.
sucrose.

Simple
and
evaporation
this
Sugar
easily
from
Extraction
1
Cane
2
The
of
sugar
stalks
leaves
are
3
A
4
The
chips
5
The
sugar
slightly
on
sugar
sugar
stalks
are
cane
cleaned
acidic
substance
with
few
crystals
juice
by
jets
and
of
sent
water
to
to
the
factory.
remove
soil,
and
the
off.
cuts
crushed
cane
treacle-like
harvested
machine
are
a
overheating.
cane
are
stripped
shredding
leaves
chars
juice
green
and
up
the
rolled
extracted
stalks
flat
from
suspension.
into
under
the
The
small
a
spray
crushing
fibrous
chips.
of
and
material
hot
water.
rolling
is
(bagasse)
a
is
removed.
Figure
2.6.1
Sugar
cane
plants
6
DID
YOU
Calcium
hydroxide
some
the
of
from
first
cane
originally
south-east
brought
to
Christopher
Asia.
the
It
was
to
neutralise
impurities
the
form
acidity
a
and
sediment.
remove
This
is
but
it
clarification.
Caribbean
Columbus
did
called
Filtration
in
not
impurities
are
removed
by
a
continuous
filtration
process
the
in
1490s,
The
came
Non-sugar
by
added
KNOW?
process
Sugar
is
impurities.
special
industrial
filters.
This
leaves
a
syrup
containing
about
85%
become
water.
important
economy
in
the
until
Caribbean
the
Dutch
Evaporation
introduced
1625.
sugar
In
crop
the
cane
cotton
it
and
from
Brazil
following
rapidly
in
as
century,
the
the
major
Caribbean.
The
syrupy
boilers
boiler
sugar
extract
(evaporators)
the
getting
water.
18
(boiling)
about
replaced
tobacco
produced
in
pressure
charred.
is
The
in
is
passed
order
to
decreased.
successively
concentrate
This
concentrated
is
to
juice
into
it.
In
prevent
then
three
each
the
contains
or
four
successive
sugar
about
from
35%
Crystallisation
DID
1
This
takes
place
under
vacuum
in
a
crystallisation
pan,
where
is
evaporated
until
it
is
saturated
with
single
A
few
crystals
of
sugar
are
added
to
help
more
sugar
crystals
to
in
a
to
form.
The
mixture
with
sugar
then
centrifuge
speeds.
and
The
a
thick
syrup
called
molasses
day
5
can
tonnes
harvest
but
sugar
machines
sugar
tonnes
of
as
a
cane
cane
developed
can
crop
day.
together
crystals.
Centrifugation
A
contains
as
harvest
300
3
worker
sugar.
much
2
KNOW?
the
A
syrup
YOU
is
a
and
machine
force
separates
drying
of
them
the
that
spins
spinning
from
lighter
round
pulls
and
heavier
particles.
This
round
at
particles
process
very
high
downwards
is
called
centrifugation
1
A
basket
centrifuge
(Figure
2.6.2)
is
used
to
separate
the
Per forated
Molasses
molasses
from
the
sugar
crystals.
The
mixture
is
placed
in
the
basket
+
perforated
basket
round
high
at
a
(a
basket
with
tiny
holes
in
it).
basket.
The
molasses
This
is
sugar
spun
speed.
Sugar
2
The
sugar
through
3
The
remains
the
sugar
in
holes
crystals
the
in
the
are
are
forced
out
basket.
dried
in
air
Molasses
using
a
type
of
tumble-drier.
Figure
2.6.2
Simplified
show
the
basket
CALCIUM
Shredder
CANE
Crusher
TIP
revis
ing
extra
ction
BAGASSE
on
the
points
SUCROSE
Vacuum
to
cr ystalliser
most
(evaporators)
separa
tion
filtrat
ion,
Flow
chart
for
the
extraction
of
sugar
from
sugar
cane
–
only
stages
are
and
1
relev
ant
techn
ique
s:
precip
itatio
n,
unde
r
shown.
vacu
um ,
KEY
are
the
treat
men
t
main
impo
rtant
which
MOLASSES
2.6.3
suga
r
conc
entra
te
Boilers
Centrifuge
Figure
a
centrifuge
Filter
Clarifier
When
RAW
to
behind
HYDROXIDE
EXAM
SUGAR
diagram
idea
crysta
llisa
tion
centrif
ugat
ion.
POINTS
The
main
stages
precipitation,
in
sucrose
treatment
extraction
under
are
vacuum,
filtration,
crystallisation
and
centrifugation.
2
Calcium
from
3
The
hydroxide
the
sugar
sugar
reduced
is
cane
solution
is
used
and
to
to
neutralise
precipitate
concentrated
by
the
juice
extracted
impurities.
evaporation
under
pressure.
4
Crystallisation
is
5
Sugar
are
crystals
done
under
separated
vacuum.
from
molasses
by
centrifugation.
19
2.7
Chromatography
use
of
a
and
separating
funnel
Paper
LEARNING
Paper
At
the
end
chromatography
OUTCOMES
of
this
topic
chromatography
dissolved
should
be
able
different
describe
chromatography

describe
the

explain
substances.
The
used
to
method
is
separate
often
a
mixture
used
to
use
of
pigments
and
inks.
of
mixture
a
Figure
of
(coloured
2.7.1
shows
coloured
compounds)
present
how
out
to
carry
in
food
paper
the
colourings
dyes.
a
funnel
how
the
different
chromatography
a
chromatography
b
c
Solvent
and
of
separate
to:

separating
is
you
use
of
a
front
separating
Lid
funnel
depend
differences
in
on
the
solubility
of
the
Chromatography
components
in
the
solvents
paper
used.
Datum
M
A
B
line
M
C
A
B
C
Solvent
Chromatography
Figure
2.7.1
Paper
chromatography:
chromatography,
EXAM

Y
ou
1
mus
t
datu
m
becaus
draw
the
line
e
you
the
lead
disso
lve
If
in
use
differe
nt
ink
the
a
spotting
finished
the
paper,
b
starting
the
chromatogram
TIPS
Draw
a
pencil
line
in
does
hite
(a
line)
type
of
on
a
piece
of
fine-grained
fi lter
paper).
ink ,
2
Put
a
spot
of
using
a
very
Small
spots
concentrated
fine
glass
dye
tube
mixture,
(capillary
M,
on
the
datum
line
tube).
no t
so lven
t.
3
the
co lou
rs
woul
d
datum
paper
penc
il
grap
the
(the
the
chromatography
in
c
tank
move
are
in
up
the
of
dye
pure
substances,
mixture,
can
also
e.g.
be
A,
B
and
placed
on
C,
that
the
you
datum
think
line
for
comparison.
the
the
in
4
A
chromatography
tank
is
set
up
with
the
solvent
level
below
the
paper!
datum

Y
ou
mus
t
that
is
the
below
line.
mak
e
so lven
t
the
O ther
sure
5
As
6
The
m
paper
off
so lven
t
into
and
separa
te.
spots
the
woul
d
dyes
A
is
on
dyes.
and
up
the
paper,
the
dyes
separate.
removed
when
the
solvent
front
is
near
the
top.
the
chromatogram
can
be
compared
with
those
of
For
C
as
example,
well
as
a
in
Figure
third
2.7.1(c),
the
mixture,
M,
contains
dye.
no t
We
can
identify
particular
solvent
20
moves
woul
d
known
wash
solvent
the
The
compo
nent
s
the
level
datu
wise
line.
the
solvent,
front.
components
they
travel
a
in
the
certain
mixture
distance
because,
for
compared
a
with
the
How
chromatography
works
DID
The
separation
of
the
components
in
the
mixture
depends
on
YOU
KNOW?
the
Substances
solvent
or
mixture
of
solvents
coloured

With
a
single
depends
on
attraction
attracted
solvent,
the
of
the
more
the
solubility
separation
of
the
component
to
the
that
paper
to
of
the
components
component
the
move
paper.
more
in
the
Components
slowly
in
solvent
up
the
a
mixture
and
that
the
by
In
a
mixture
of
two
dried,
solvents,
one
solvent
is
attracted
to
the
strongly
than
the
other.
If
a
component
in
the
dye
is
then
in
the
solvent
that
is
more
strongly
attracted
to
will
the
to
not
dye
the
move
is
more
paper,
it
as
fast
during
soluble
will
in
move
the
chromatography.
solvent
faster
that
during
is
If
less
the
a
that
with
reacts
of
the
A
a
separating
separating
different
funnel
densities.
is
the
mixture
to
compounds.
we
use
as
a
The
spray
a
locating
is
agent.
in
attracted
chromatography.
a
Using
a
with
paper,
component
strongly
paper
more
called
it
After
the
sprayed
coloured
compound
soluble
separated
paper
form
more
not
be
chromatography.
compound
paper.
still
chromatography,
is
are
can
components

are
used.
b
funnel
used
Immiscible
to
separate
liquids
are
immiscible
liquids
that
liquids
do
that
not
have
mix.
Oil
Figure
We
a
2.7.2
can
use
solvent.
shows
a
An
how
we
separating
example
is
use
funnel
a
a
separating
to
separate
solution
of
funnel.
two
iodine
solutes
and
dissolved
potassium
in
Water
Oil
iodide
Tap
in
water
in
water,
hexane.
(see
Figure
but
We
following
2.7.3).
potassium
can
Iodine
iodide
separate
the
is
is
more
more
iodine
soluble
soluble
from
the
in
in
hexane
water
than
than
potassium
in
iodide
in
the
way:
Water
1
Put
the
solution
of
iodine
and
potassium
iodide
in
a
separating
funnel.
Figure
2.7.2
a
A
mixture
water
2
Add
hexane
to
the
separating
funnel
(hexane
is
immiscible
is
of
oil
allowed
and
to
settle
with
into
two
layers.
b
The
water).
lower,
off
3
Shake
4
Most
of
iodide
5
The
the
contents
the
iodine
remains
layer
of
in
of
the
funnel
moves
the
to
the
to
mix
the
hexane
layer
and
the
in
potassium
the
hexane
KEY
iodide
in
water
is
layer
is
run
beaker.
run
off,
leaving
POINTS
the
Paper
chromatography
is
layer.
used
of
to
two
solutes
Separating
the
potassium
water.
1
iodine
denser
into
solutions.
2
funnel
In
a
Solution
of
separate
or
in
paper
solvent
more
a
a
mixture
different
solution.
chromatography,
carries
the
iodine
components
of
the
mixture
Shake
Hexane
in
hexane
up
the
paper
at
different
rates.
Solution
iodide
in
of
and
3
potassium
Solution
iodine
iodide
of
in
Paper
can
water
water
4
2.7.3
When
a
solution
of
iodine
and
potassium
iodide
in
water
is
be
used
to
identify
components
in
A
funnel
to
Figure
chromatography
potassium
separating
separate
two
a
the
mixture.
is
used
immiscible
shaken
liquids.
with
hexane,
the
iodine
moves
to
the
layer
of
hexane.
21
3
Atomic
3.1
The
LEARNING
At
the
structure
end
Subatomic
particles
An
smallest
be
of
this
topic
able
describe
atoms
the
in
atom
is
the
change.
uncharged
Atoms
are
made
particle
up
of
that
even
can
take
smaller
part
in
particles.
a
We
to:
structure
terms
neutrons
atoms
you
call

of
OUTCOMES
chemical
should
structure
and
of
these
particles
subatomic
particles.
of

At
the

The
centre
of
each
atom
is
a
tiny
nucleus
protons,
nucleus
contains
two
types
of
subatomic
particle:
protons
and
electrons
neutrons

describe
the
arrangement
of

electrons
in
atoms
in
Around
the
outside
of
the
atoms
are
subatomic
particles
called
shells
electrons

explain
the
term
atomic

The
electrons
are
arranged
in
electron
shells
(also
called
energy
number
levels).

describe
with
illustrations
the

structures
of
atoms
of
In
of
number
1
to
a
neutral
atom,
the
number
of
electrons
to
the
have
years.
these
We
models,
because
further
developed
can
it
is
draw
difficult
sometimes
away.
different
different
they
Figure
to
are
3.1.1
models
models
of
of
the
the
show
the
exact
nearer
the
nucleus
shows
two
useful
a
atom
atom.
position
and
over
In
of
the
the
were
past
of
electrons
sometimes
models
of
an
atom.
b
Electrons
KNOW?
atom
the
each
Electron
If
number
20.
100
YOU
equal
protons.
Scientists
DID
is
atomic
the
size
of
the
orbit
nucleus
a
Proton
cricket
field,
be
size
the
of
sand.
Nearly
atom
is
density
in
of
the
its
large
the
would
grain
mass
nucleus.
the
unbelievably
a
all
nucleus
nucleus
So
of
of
the
the
must
be
Neutron
huge!
Nucleus
The
nucleus
protons
Figure
3.1.1
a
Model
atom
Putting

The

Each

The
atoms
two,
The
22
of
of
periodic
of
in
protons
the
the
(proton
lithium
order
of
an
atom
showing
electrons
the
moving
contains
neutrons
electrons
around
in
the
shells,
b
model
of
an
nucleus
order
in
the
nucleus
of
an
atom
is
called
the
number.
atom
number

elements
number
atomic
of
showing
and
same
elements
number).
three
table
their
element
and
is
an
atomic
so
can
has
be
the
same
arranged
Hydrogen
has
in
one
number
order
of
of
proton,
protons.
their
helium
atomic
has
on.
arrangement
number.
See
of
4.1
all
for
the
elements
more
known,
information.
in
Electron
shells
2nd
In
one
model
of
the
atom,
the
electrons
move
at
high
speed
electron
at
shell
certain
have
distances
the
shape
electrons
electron

The
in
of
a
(see
shell
is
the
nucleus
sphere.
circular
shells
first
from
orbits
a
vague
simplified
around
Figure
nearest
In
in
the
regions
model
nucleus.
of
we
These
space
that
show
the
orbits
are
Nucleus
the
3.1.2).
the
nucleus.
It
holds
a
maximum
of
two
electrons.
1st

The
second
shell
is
further
away
from
the
nucleus.
It
holds
electron
a
shell
maximum
of
eight
electrons.
3rd

The
third
second
shell
shell
is
even
has
further
eight
away.
It
starts
filling
up
when
the
electron
Figure
shell
3.1.2
In
electrons.
the
three
The
electron
arrangement
of
elements
1
to
electron
arrangement
configuration
or
electronic
in
an
atom
structure)
is
(also
called
deduced
by
the
electron
adding
at
a
time
to
the
shells,
starting
with
the
inner
shell.
the
number
protons.)
We
separated
by
of
write
electrons
the
commas.
in
an
number
For
of
atom
equals
electrons
in
the
each
number
shell
shou
ld
as
draw
the
of
a
structu
res
number
elem
ents
example:
Hydrogen
atom:
1
proton,
so
1
electron.
The
electron
goes
into
shell,
so
the
electron
arrangement
is
of
Helium
atom:
2
protons,
so
2
electrons.
Both
electrons
go
into
2,8,8,
2.
shell,
so
the
electron
arrangement
is
Lithium:
3
protons,
so
3
electrons.
T
wo
electrons
go
into
the
but
this
shell
is
then
full,
so
the
third
electron
goes

shell.
Sodium:
shell
and
shell
is
11
Therefore
protons,
eight
full,
so
the
so
11
electrons
the
electron
eleventh
arrangement
electrons.
into
the
T
wo
second
electron
goes
is
into
go
Then
into
the
into
the
third
The
the
electron
shown
in
electron
arrangement
arrangements
Figure
of
the
is
atoms
doin
g
that
the
given
table
in
a
num
ber
in
the
equa
ls
the
the
of
2,1.
electrons
shell.
their
first
the
electr
ons.
first
second
shell.
KEY
Therefore
When
atom
,
pro ton
s
num
ber
second
20
num
bers,
2.
perio
dic
shell,
first
the
of

how
give
remem
ber
neut
ral
first
the
in
1.
this,

know
electr
onic
the
e.g.
first
in
shells.
and
structu
res

the
TIP
(Remember
to
that
atom
arranged
electrons,
Y
ou
one
are
20
EXAM
The
sodium
electrons
POINTS
2,8,1.
of
the
first
20
elements
are
1
The
of
3.1.3.
nucleus
all
is
atoms.
protons
and
in
It
the
centre
contains
neutrons.
2
1
2
The
electrons
speed
2
1
4
6
5
7
9
8
and
are
In
neutral
a
number
Li
Be
B
C
N
O
F
Ne
2,1
2,2
2,3
2,4
2,5
2,6
2,7
2,8
the
13
12
14
15
16
17
Na
2,8,1
Mg
Si
P
S
Cl
Ar
2,8,2
2,8,3
2,8,4
2,8,5
2,8,6
2,8,7
2,8,8
20
5
K
Ca
2,8,8,1
2,8,8,2
3.1.3
The
6
electron
arrangements
of
the
first
20
arranged
of
atom
in
shells.
the
electrons
number
The
first
hold
Al
The
to
Figure
high
of
equals
protons.
18
4
19
at
nucleus
10
3
11
the
He
H
3
move
outside
8
up
electron
to
2
second
shell
can
electrons.
shell
can
hold
up
electrons.
The
electron
can
be
arrangement
written
in
numbers.
elements
23
3.2
Protons,
and
electrons
Properties
LEARNING
the
end
of
this
topic
be
able
explain
the
neutrons
that
electrons,
neutrons
mass,
position

explain
in
in
terms
charge
the
the
each
other.
term
the
neutrons
can
to
be
are
This
and
The
is
called
electrons
number,
number,
to
different
masses.
compare.
So
we
They
weigh
compare
the
relative
mass.
ionic
also
differ
in
electric
charge.
Electric
or
negative.
We
also
measure
the
charges
differences
are
shown
in
T
able
3.2.1.
3.2.1
Relative
masses
and
charges
of
protons,
neutrons
and
electrons
for
Where
found
Symbol
for
Relative
Relative
mass
charge
showing
the
particle
mass
charge
Proton
Nucleus
p
1
+1
Neutron
Nucleus
n
1
No
Electron
Outside
e
0.00054
−1
and
symbol.
the
charge
nucleus
DID
YOU
KNOW?
−27
The
are
mass
of
about
kilogram
than
as
Mak
e
your
of
it.
sure
way
the
the
that
you
around
table
to
only
1.7
×
10
kg.
This
have
having
means
that
protons
in
there
a
protons!
even
proton!
no
is
relative
usua
lly
periodi
c
atom
ic
table
Counting

the
Atoms
of
element
In
smaller
some
mass
at
all
mass,
theories
and
being
of
over
science
behaving
1000
the
more
times
electrons
like
light
lighter
are
taken
waves.
subatomic
particles
out
each
from
–
Hydrogen
–
Carbon
–
Lithium
–
Calcium
element
others.
has
the
have
For
their
own
symbol
to
distinguish
the
example:
symbol
H
atom
ic
show
n
as
well
has
the
symbol
C
on
has
the
symbol
Li
as
num
ber
.

For

Atoms

more
has
the
about
of
symbol
symbols
different
Ca
see
elements
The
number
of
protons
is
The
number
of
protons
+
called
its
mass
neutrons,
24
is
know
the
get
infor
mation
T
he
mass
proton
TIP
periodi
c
most
a
a
600 000 000 000 000 000 000 000 000
of
Electrons
EXAM
so
their
other.
particle
atomic
have
difficult
mass
notation
ions
and
positive
each
Subatomic
atoms
electrons
and
atom
T
able
interpret
and
numbers
of
number

the
to
relative
relative
electrons
protons
charge
and
and
differences
Protons,
between
neutrons
to:
masses

protons,
you
little
should
of
OUTCOMES
Protons,
At
neutrons
its
number.
mass
4.1.
have
the
atomic
the
So
number
is
different
if
number
number
an
23.
numbers
of
atom
(see
11
protons.
3.1).
neutrons
has
of
in
an
protons
atom
and
is
12

The
number
of
electrons
in
a
neutral
atom
equals
the
number
of
a
+
protons.

Positively
charged
ions
are
atoms
that
have
lost
one
or
3
+
more
3
+
+
electrons.
+

Negatively
charged
ions
are
atoms
that
have
gained
one
or
more
Li
Li
+
e
electrons.
2–
b
A
simple
notation
for
atoms
8
+
We
can
the
following
show
the
mass
number,
atomic
number
and
symbol
+
2
8
+
2e
O
using
notation:
2–
O
Mass
+
number
Figure
40
Element
Ca
3.2.1
a
symbol
A
lithium
one
atom
electron
to
has
form
lost
a
20
lithium
Atomic
(proton)
atom
number
ion.
has
electrons
oxide
We
can
extend
this
to
ions
as
shown
many
number
neutrons?
of
boron,
neutrons
=
mass
number
−
atomic
number
=
mass
number
−
proton
number
for
example,
using
the
notation
above
with
a
POINTS
Protons
of
have
a
positive
mass
charge,
number
an
S
1
in
form
ion.
16
KEY
So
to
oxygen
two
2–
32
Na
11
How
An
below:
+
23
b
gained
electrons
have
11:
a
negative
neutrons
11
charge
are
and
uncharged.
B
5
2
Protons
and
neutrons
(approximately)
there
are
5
protons
and
11
−
5
=
6
the
have
same
neutrons.
mass.
Electrons
are
much
lighter.
How
many

a
electrons?
3
For
negative
ion:
add
the
number
of
charges
to
the
number
Mass
of
electrons
in
the
neutral
atom
(=
number
of
protons).
So
for
number
is
the
number
of
protons
+
neutrons.
the
4
ion:
Number
number
of
–
neutrons
atomic
=
mass
number.
3–
14
N
5
For
negative
ions,
number
of
7
electrons
plus
there
are
7
+
3
=
10
For
a
positive
ion:
subtract
the
number
of
charges
from
the
electrons
in
the
of
number
charges.
positive
neutral
atom.
So
for
the
2+
Cu
=
number
proton
of
number
ion:
minus
64
ions,
number
electrons
of
proton
electrons.
For

=
number
6
We
number
can
write
notation
for
of
a
charges.
simple
atoms
using
29
subscripts
there
are
=
29
–
2
=
27
and
superscripts.
electrons.
25
3.3
Isotopes
Isotopy
LEARNING
OUTCOMES
Atoms
At
the
end
of
this
topic
of
protons,
should
be
able
i.e.
atoms
have
different
define

describe
atomic
terms
the
isotopy
notation
number
of
list
have
number.
the
In
same
most
number
elements,
of
some
of
the
of
numbers
atoms
of
neutrons
to
others.
We
of
protons
call
these
isotopes.
are
of
atoms
with
neutrons.
the
So
same
isotopes
number
are
atoms
with
the
but
different
same
atomic
entity
three
uses
of
radioactive
define
using
relative
atomic
on
the
different
standard
after
mass
numbers.
notation
their
name,
we
e.g.
We
used
in
usually
3.2
carbon-14,
or
describe
by
writing
isotopes
the
mass
uranium-235.
mass
The
based
but
the
number
isotopes

always
atomic
items
number

different
forms
numbers
the
element
same
in
Isotopes
in
same
the
to:

of
the
you
three
isotopes
of
hydrogen
are
shown
in
Figure
3.3.1.
carbon-12
isotope.
Neutron
Electron
Proton
Hydrogen
has
Deuterium
atom
has
1 proton
and
H
DID
YOU
the
same
chemical
relative
found
mass
atomic
mass
by
first
percentage
of
each
by
the
isotope,
mass
mass
number
get
For
the
then
Then
adding
average
mass
consists
chlorine-37
the
divide
by
of
isotope
chlorine-35
relative
×
the
properties
hydrogen
mass
hydrogen-1.
atomic
37)
+
per
25%
and
isotope.
mass
(75
atomic
of
atoms.
atoms
but
of
hydrogen-1
Isotopes
may
have
of
the
and
same
different
deuterium
element
physical
atom.
of
the
properties.
mass
an
×
this
atom
is
so
problem,
small
we
that
have
to
you
cannot
weigh
a
weigh
sample
it.
To
containing
a
lot
But
there
we
may
weigh,
so
be
a
the
number
average
of
different
mass
of
an
isotopes
atom
will
among
be
all
slightly
So
from
the
atomic
mass.
We
define
the
of
naturally
of
carbon-12
relative
occurring
has
a
atomic
atoms
mass
of
of
mass
an
as
the
element
exactly
12
weighted
on
a
scale
average
where
an
mass
atom
units.
the
75%
of

An
average

The
is
used
because
most
elements
are
a
mixture
of
isotopes.
the
‘weighted
average’
means
that
you
have
to
take
into
is

35)
The
amount
of
symbol
for
each
isotope
relative
present.
atomic
mass
is
A
r
=
35.5
average
100

A
of
element
E
mass
of
isotopes
of
element
E
=
r
×
12
26
has
have
to
the
(25
times
of
of
them
100
example:
Chlorine
isotopes
of
different
together
.
three
isotope
the
the
H
1
multiplying
of
present
3
can
overcome
the
2 neutrons
KNOW?
The
be
three
twice
Relative
The
and
H
The
atom
1 proton
1
3.3.1
has
has
2
1
Tritium
Tritium
1 neutron
1
Figure
atom
1 proton
mass
of
one
atom
of
carbon-12
account
Atomic
notation
Molecules
have
two
such
as
atoms.
in
simple
chlorine
We
can
and
molecules
oxygen
show
this
by
are
diatomic.
including
a
Their
figure
2
EXAM
molecules
as
Y
ou
subscript
at
the
bottom
right
of
the
symbol.
Compare
the
TIP
a
do
no t
notation
de tails
for
several
chlorine
chlorine-37
in
molecules
their
with
isotopes
chlorine-35
and
only
a
The
b
A
chlorine
mass
A
of
chlorine
chlorine
mass
35
Cl
formula
35
Cl
for
notation
molecule
of
a
for
with
two
with
one
37
Cl
37
Cl
molecule
has
a
relative
chlorine
the
of
in
a
chlorine
to
of
iso to
pes.
molecule
chlorine-35
has
a
relative
molecule
with
atom
mass
two
of
of
chlorine-35
and
one
atom
of
72.
atoms
DID
of
chlorine-37
has
a
relative
YOU
Nuclear
KNOW?
power
radioactive
and
its
energy
uses
is
isotopes,
called
radioactive
isotopes,
have
unstable
break
down
(decay).
As
the
nucleus
decays,
it
gives
out
to
alpha
or
beta
particles)
or
rays
(gamma
from
a
sample
decreases
over
time.
This
fuel.
in
heat
a
as
Heat
series
energy
of
boil
water
.
The
is
resulting
powers
turbines
to
radiation).
turn
radioactivity
a
tiny
steam
(called
as
use
such
nuclei,
used
particles
stations
isotopes
released
processes.
The
you
molecule,
isotopes
atoms
Cl
74.
Radioactivity
which
of
sylla
bus
uses
radioa
ctive
37
Cl
three
uranium-235
Some
T
he
70.
chlorine-37
A
the
learn
types
requi
res
know
35
b
3.3.2
to
Cl
2
Figure
need
the
radiat
ion.
atoms:
a
of
Measuring
generators
that
generate
this
electricity.
rate
has
found
Carbon
The
many
uses.
dating
atmosphere
contains
carbon
dioxide.
The
carbon
in
this
is
KEY
mainly
carbon-12
carbon-14
(which
carbon-14
atoms
bone
from
amount
of
an
(which
is
is
non-radioactive)
radioactive).
are
absorbed
organism
carbon-14
which
When
into
was
the
an
but
organism
body.
once
there
The
living
also
dies
age
can
is
be
of
no
new
wood
found
POINTS
some
1
or
from
Isotopes
same
the
but
present.
are
atoms
number
different
of
with
the
protons
numbers
of
neutrons.
2
The
relative
atomic
mass
is
Radiotherapy
the
Cancer
cells
radiation
divide
can
be
more
used
to
rapidly
kill
than
cancer
normal
cells
in
cells.
the
Beta
affected
or
weighted
of
naturally
of
an
radioactive
position
in
the
isotopes
body
can
be
can
be
injected
observed
using
into
the
special
body
and
equipment.
element
of
tracers
an
on
atom
a
of
scale
carbon-12
is
to
see
how
well
the
thyroid
gland
is
a
mass
of
exactly
12
units.
their
One
3
use
mass
atoms
tracers
has
Specific
occurring
area.
where
Radioactive
average
gamma
Radioactive
isotopes
have
working.
unstable
form
nuclei
different
and
decay
to
atoms.
Pacemakers
4
Heart
pacemakers
can
be
powered
by
‘batteries’
of
Radioactive
be
The
heat
energy
liberated
during
radioactive
decay
isotopes
generates
used
in
carbon
dating,
an
radiotherapy,
electric
can
plutonium-238.
as
radioactive
current.
tracers,
in
in
energy
pacemakers
and
generation.
27
4
The
periodic
table
and
periodicity
4.1
The
Early
LEARNING
periodic
developments
OUTCOMES
Döbereiner’s
At
the
end
should
be
of
this
able
topic
describe
the
In
to:
1817,
Johann
of
the

periodic
linked
called
table
these
the
basis
arrangement
table
in

describe
the
and
the
periodic
and
of
terms
number
in
of
the
of
suggested
groups
of
three
that
elements
(triads).
could
be
He:
in
an
For
increase
in
example:
their
atomic
chlorine
(35),
weights
bromine
(now
(80)
and
(127)

deduced
atomic
of
structure
arrangement
table
with
masses).
the
periodic
atomic
atomic
triads
atomic
iodine
describe
Döbereiner
together
historical
development

‘triads’
you
grouped

table

of
the
the
middle
that
was
elements
the
of
average
many
of
the
of
the
first
triads
and
had
third
an
elements
triad
suggested
lithium,
periods
that
weight
that
some
sodium
and
triads
had
potassium
similar
but
chemical
others
did
properties,
e.g.
not.
groups.
Newlands’
Between

listed

noted
‘law
1863
and
elements
that
elements
of
in
in
based

listed

arranged
his
so
elements
gaps
that
iodine,

their
elements
periodic
developed
reasoning
the
(horizontal
left
of
Newlands:
atomic
were
weights
separated
by
intervals
of
eight
table
his
first
periodic
table
of
the
elements
He:


order
John
(octaves).
Mendeleev
1869.
1866,
similar
Mendeleev’s
Dmitri
octaves’
in
order
elements
the
table
elements
showed
chemical
of
in
characteristics
atomic
weights
(masses)
groups
(vertical
columns)
and
periods
rows)
in
fell
on
in
that
where
with
the
similar
same
there
elements
was
properties,
vertical
a
had
not
e.g.
yet
been
chlorine,
discovered,
bromine
and
groups
gradual
change
in
properties
across
a
period.
The
Figure
4.1.1
Mendeleev’s
periodic
several
first
table.
forms
developed
the
The
gradually
second
been
The
the
modern
form
periodic
28
today.
table
periodic
table
4.1.2
shows
the
modern
periodic
table.
has
table
modern
we
features:
know
periodic
developed
The
into
the
periodic
Figure
table.
of
published
He
of
structure
extended
form
of
the
periodic
table
has
the
following
0
Group
numbers
Group
Relative
atomic
mass
1
number
1
numbers
4
H
Atomic
7
He
2
9
11
Li
Be
3
4
23
24
Transition
Mg
39
45
19
85
20
21
88
89
Rb
38
37
Cs
57
226
Fr
42
181
186
73
74
Ac
88
108
45
46
47
195
197
77
78
31
115
48
201
80
119
122
128
Sn
Tl
4.1.2
The
Elements
are
elements
in
Elements
58–71
and
90–103
(all
metals)
have
been
modern
periodic
arranged
Group
Mendeleev’s
Metalloids
table
elements
to
long
in
groups
numbered
I–VII
and
0.
Mendeleev
0,
the
noble
gases,
were
discovered
was
in
Group
Groups
II,
three
in
I
have
similar
chemical
properties.
The
weights,
Across
groups
and
each
Across
to
period
are
called
short
periods
and
the
others
are
Between
some
the
there
is
a
gradual
change
in
properties
of
the
A
group
2
such
and
the
as
3
there
boiling
metals
properties
basis
of
elements
the
in
of
and
the
is
a
similar
change
in
The
periodic
is
The
outer
non-metals
These
are
are
called
periodic
periodic
table
electron
shell
the
elements
that
column
table.
A
4
order
In
the
are
arranged
arrangement
electrons
of
determines
same
group
have
the
of
table
is
in
an
order
atom,
of
the
row.
arranged
same
number
of
number
.
form
table,
in
of
the
atoms
each
characteristic
of
group
number
have
of
their
especially
chemical
atomic
short
elements
table
properties
outer
shell
electrons,
usually
the
to
the
group
number.
of
5
the
horizontal
have
metalloids.
element.
in
a
periodic
in
equal
Elements
vertical
physical
outer
of
a
point.
the
both.
modern
the
number.
number
is
from
a

differences
properties
periodic
an
show
elements.
3
atomic
to
and
non-metallic.
Periods
properties
The
their
0.
period
The
of
arranging
same
in

order
after
periods.
metallic

the
published.
VII
periods
arranged
The
2

Rn
86
POINTS
in
first
At
85
table
similarities
The
54
222
Non-metals
the

Xe
53
210
omitted
atomic
applies
131
I
Po
elements
The
127
84
83
Kr
36
89
1

84
35
52
Bi
82
80
Br
210
209
Pb
81
18
T
e
51
207
KEY

Sb
50
204
Hg
79
34
Ar
17
Se
33
40
Cl
79
As
32
In
49
35.5
16
75
Ge
10
S
15
73
Ga
Cd
Au
Pt
Ir
76
112
Ag
Pd
192
Metals
Figure
106
70
Zn
30
190
Os
75
29
44
Re
W
T
a
72
43
184
28
Rh
65
Cu
32
P
14
Ne
9
227
Ra
87
41
Hf
La
56
223
40
178
103
Ru
63.5
Ni
27
101
T
c
59
Co
26
98
Mo
59
Fe
25
96
Nb
56
Mn
24
93
Zr
55
Cr
23
91
139
Ba
55
52
V
22
39
137
51
Ti
Y
Sr
133
48
Sc
Ca
31
20
F
8
Si
13
40
K
29
19
O
7
Al
12
16
N
6
27
metals
14
C
5
Na
11
12
B
The
period
number
element
is
the
shells
an
of
an
number
of
shell
of
element’s
atom
electrons.
that

For
Groups
I–VII
the
number
of
outer
shell
electrons
is
equal
to
6
group
Elements
Metals
in
Group
0
generally
have
eight
electrons
in
their
the
Helium,
Atoms
in
the
first
period
has
two
electrons
in
its
outer
of
elements
in
the
same
period
have
their
are
electrons
the
in
the
same
period
number
and
left
found
on
the
non-
right.
There
are
trends
in
the
outermost
of
elements
down
shell.
each
The
on
table
shell.
properties

found
outermost
7

are
periodic
metals
shell.
electrons.
number.
of

contain
the
of
an
element
is
the
number
of
shells
of
group
and
across
each
an
period.
element’s
atom
that
contain
electrons.
29
4.2
Trends
Physical
LEARNING
the
end
of
this
topic

be
able
describe
of
Group
the
Group
II
II
elements
physical
the
down
the
of
II
metals
show
some
general
group.
to:
trends
in
physical
T
able
properties
properties
you
trends
should
properties
Group
OUTCOMES
The
At
in
of
the
Group
4.2.1
Physical
properties
of
Group
II
elements
II
Element
Melting
Density
point
(g cm
Radius
of
elements
–3

describe
the
reactions
magnesium
with
water,
and
air
hydrochloric
Beryllium
describe
trends
dilute
(Be)
Magnesium
in
of
Group
II
explain
Group
ease
trends
II
of
in
reactivity
650
1.74
0.160
838
1.55
0.197
768
2.6
0.215
714
3.5
0.217
(Mg)
(Ca)
elements
(Sr)
in
terms
(Ba)
of
reactions
in
Group
Reaction
EXAM
with
II
are
Group
more
II
reactive
elements
going
down
the
group.
oxygen
metals
descending
may
be
data
in
group,
air
and
the
even
metals
more
burn
rapidly
more
in
oxygen.
readily.
The
On
reactions
similar,
forming
the
metal
2Ca(s)
+
O
(g)
→
2CaO(s)
2
that
calcium
trend
oxide.
from
Rem
embe
r
gene
ral
burn
the
requi
red
are
anal
yse
tables
.
II
of
TIP
Group
a
0.122
ionisation.
Metals
Y
our
1.85
of
Some
to
1280
elements
Barium

(nm)
the
Strontium
reactivity
atom
acid
Calcium

)
of
calcium
and
(ºC)
oxygen
calcium
does
oxide
no t
is
have
to
goin
g
in
direc
tion
the
II
towa
rds
points
the
the
that
same
For
more
information
Reaction
For
gene
ral
Grou
p
one
writing
equations
see
6.2.
trend
of
elem
ents
lower
with
in
the
is
Group
II
metals
react
with
water.
The
reactivity
increases
down
group.
Magnesium
reacts
slowly
with
cold
water:
melt
ing
Mg(s)
you
grou
p.
water
exam
ple,
points
as
on
withou
t
except
ion.
melt
ing
be
go
+
2H
O(l)
→
Mg(OH)
2
down
magnesium
(aq)
+
H
2
water
(g)
2
magnesium
hydrogen
Mag
nesium
hydroxide
is
it
an
except
ion
has
point
a
lower
than
becaus
e
Hot
magnesium
reacts
with
steam
to
form
the
trend
Mg(s)
+
H
O(g)
→
MgO(s)
+
H
2
woul
d
oxide:
(g)
2
sugg
est.
Calcium
reacts
Ca(s)
+
more
2H
rapidly
O(l)
2
calcium
water
→
with
water
Ca(OH)
than
(aq)
2
calcium
hydroxide
30
magnesium
melt
ing
+
magnesium:
H
(g)
2
hydrogen
the
Reaction
Group
salts
II
with
metals
called
down
hydrochloric
the
react
with
chlorides.
The
acid
hydrochloric
reactions
are
acid
to
similar.
form
The
hydrogen
reactivity
and
increases
group.
Mg(s)
+
2HCl(aq)
→
MgCl
(aq)
+
H
2
magnesium
Ca(s)
magnesium
acid
chloride
+
2HCl(aq)
→
CaCl
hydrogen
(aq)
+
H
2
calcium
(g)
2
hydrochloric
(g)
2
hydrochloric
calcium
hydrogen
acid
chloride
Figure
4.2.1
Magnesium
ribbon
rapidly
the
the
Reactivity
and
ease
of
reactivity
of
the
Group
II
metals
is
linked
to
the
ease
they
form
ions.
When
YOU
they
react,
their
atoms
lose
their
KNOW?
electrons
to
form
in
chemical
reactions
two
within
outermost
in
air.
with
Similarities
which
reacts
oxygen
ionisation
DID
The
with
a
group
are
not
always
ions.
simple.
When
magnesium
2+
Mg
→
Mg
+
2e
burns
oxide
The
energy
needed
to
remove
an
electron
from
an
atom
or
ion
in
air
,
that
the
ionisation
energy.
T
able
4.2.2
shows
that,
as
you
the
group,
the
energy
needed
to
remove
the
two
not
only
A
the
small
of
magnesium
nitride
go
is
down
is
formed.
is
amount
called
it
is
also
formed
by
reaction
with
electrons
nitrogen
in
the
air
.
decreases.
T
able
4.2.2
Energy
needed
Group
II
to
remove
the
two
electrons
from
the
outer
shell
of
KEY
atoms
1
Element
POINTS
Energy
needed
to
remove
There
are
general
trends
two
in
some
of
the
physical
–1
electrons
from
atom
(kJ mol
)
properties
Beryllium
2660
Magnesium
2186
Calcium
1740
Strontium
1608
Barium
1468
2
The
Group
with
in
3
pure
the
Most
with
air
an
are
three
things
which
influence
the
energy
required
to
4
electron:
Distance
of
outer
electrons
from
the
nucleus:
the
further
are
from
the
nucleus,
the
smaller
the
the
attraction
II
elements
form
Group
water
Group
II
II
to
or
react
oxygen
oxides.
elements
form
and
the
react
metal
hydrogen.
to
II
elements
hydrochloric
react
acid
to
outer
form
electrons
Group
remove
with

the
oxygen
to
hydroxide
There
of
elements.
metal
chlorides
and
the
hydrogen.
nucleus
and
the
lower
the
energy
needed
to
remove
the
outer
5
electrons.
The
II

Nuclear
charge:
the
greater
the
number
of
protons
in
the
reactivity
elements
more
energy
is
required
to
remove
the
outer
the
Group
depends
on
the
nucleus,
ease
the
of
of
ionisation
of
their
electrons.
atoms.

Inner
the
electron
outer
greater
energy
The
size
electrons.
the
number
needed
energy
of
shells
the
to
This
of
is
and
the
down
the
amount
called
inner
remove
decreases
atoms
reduce
of
nuclear
shielding
shells
of
the
outer
the
group
increased
or
charge
felt
screening.
electrons,
the
lower
by
6
The
screening
the
ease
increase
outweigh
the
in
of
from
the
nuclear
the
shielding
nuclear
on
the
of
the
nucleus,
charge
and
the
effect
of
the
outer
of
electrons
increased
ionisation
depends
distance
electrons.
because
The
atoms
the
by
inner
electron
charge.
shells.
31
4.3
Trends
Physical
LEARNING
the
end
of
this
topic
be
able
describe
Group
the
physical
state

elements
are
This
called
means
the
that
halogens.
they
have
They
all
exist
molecules
as
made
up
two
atoms.
T
able
4.3.1
shows
some
of
their
physical
properties.
4.3.1
Physical
properties
of
the
halogens
halogens
describe
the
properties

VII
molecules.
of
T
able
the
properties
to:
of

VII
you
diatomic
should
Group
OUTCOMES
The
At
in
describe
trends
of
the
reactions
of
the
in
physical
Halogen
State
halogens
at
Colour
25 ºC
displacement
halides
by
Fluorine
(F
)
Melting
Boiling
point
point
(ºC)
(ºC)
Gas
Yellow
–220
–188
Gas
Yellow-green
–101
–35
Liquid
Red-brown
–7
+59
Solid
Grey-black
+114
+184
2
halogens
Chlorine
(Cl
)
2

explain
these
displacement
Bromine
(Br
)
2
reactions
power
in
terms
(ease
of
of
oxidising
Iodine
ionisation).
(I
)
2

The
colours

Bromine
solution

The
get
darker
vapour
of
is
iodine
melting
A
displacement
or
ion
has
aqueous
to
in
the
is
+
a
in
chlorine
potassium
(aq)
points
the
vapour
potassium
boiling
another
of
potassium
Cl
iodine
down
iodide
increase
Figure
4.3.1
At
room
chlorine
is
a
temperature,
is
liquid
a
gas,
and
bromine
iodine
is
adding
and
a
the
group.
reaction
a
(a
in
which
compound.
solution
bromide,
the
of
For
one
example,
chlorine
chlorine
type
in
of
when
water)
displaces
atom
the
is
an
added
bromide
bromide:
2KBr(aq)
→
2KCl(aq)
+
Br
(aq)
2
chlorine
halogen
purple
brown.
down
2
By
is
is
group.
reactions
replaced
aqueous
ion
and
intense
but
aqueous
reaction
solution
more
red-brown
in
points
Displacement
and
different
higher
in
potassium
potassium
bromide
chloride
halogens
the
group
from
its
halide
DID
YOU
KNOW?
group
to
different
has
bromine
halides,
displaced
the
we
can
halogen
see
that
lower
in
a
the
solution.
a
solid.
DID
If
YOU
you
iodine
try
in
to
the
T
o
of
iodine
potassium
32
dissolve
water
,
insoluble.
solution
KNOW?
it
get
an
iodine,
in
a
a
crystal
appears
of
Astatine
be
follow
aqueous
we
dissolve
solution
iodide.
to
of
at
room
are
in
is
the
the
in
radioactive
form
decay
point.
below
state
temperature.
liquid
melting
halogen
trend
of
the
sufficient
Astatine
halogens,
However
,
because
is
iodine.
the
most
heat
to
samples
energy
keep
its
is
radioactive.
astatine
of
given
should
astatine
off
be
we
solid
produced
during
temperature
If
a
above
its
its
T
able
4.3.2
The
reactions
products
there
Halogen
is
are
no
of
the
given
halides
if
a
with
reaction
the
halogens.
occurs.
A
dash
The
(–)
names
of
indicates
reaction.
in
aqueous
the
that
Halide
solution
Potassium
Chlorine
chloride
Potassium
–
potassium
bromine
Bromine
–
bromide
chloride
Potassium
+
potassium
formed
iodine
–
–
Explaining
The
of
halogens
get
differences
information
ease
of
the
the
potassium
in
less
the
about
–
displacement
reactive
oxidising
oxidation
formation
of
going
see
halide
8.1
ions
we
go
down
the
of
Group
the
and
8.2.
from
VII.
This
halogens.
We
For
The
radius
of
the
can
is
because
EXAM
TIP
link
this
to
It
the
is
impo
rtant
distin
guis
h
halogens.
ens
atom
The
the

oxidising
group
The
to
an
stronger
oxidising
ability
a
oxidising
add
halogen
A
is
of
better
ability
electron
atom
is
halogens
decreases
to
a
decreases.
agent
like
halogen
than
this
atom
one
because
to
form
A
halogen
lower
it
a
is
higher
in
elem
ents.
down.
more
are
difficult
negative
ion
if
(F
will
accept
electrons
from
a
(I
weaker
Chlorine
),
So:
(stronger
oxidising
)
agent
–
better
electron
acceptor)
is
bromine
from
a
Bromine
(weaker
bromide.
oxidising
agent
–
worse
electron
acceptor)
will
ions.
chlorine
from
a
In
(Cl
)
or
accept
able
exam
ple,
howe
ver
,
to
write
,
‘chlor
ine
brom
ine
so lutio
n
),
iodid
e
answ
ering
ques
tions
,
not
a
displace
fluo rid
e
(Br
displa
ces

ic
are
Halid
es
will
fo r
displace
es.
compo
unds
chlor
ide
exam
it

ionic
brom
ide
agent
halid
diatom
that
contai
ning
the
larger.
oxidising
agent.
the
oxidising
are
increases.
mo lec
ules

to
be tw
een
and
group:
halogen
+
more
Halog
ens

bromide
formed
–
halog
As
+
reactions
down
power
chloride
formed
iodine
Iodine
iodide
of
chloride.
from
po tass
ium
brom
ide’.
KEY
1
POINTS
The
colours
down
2
The
the
boiling
increase
of
the
halogens
get
darker
and
more
intense
group.
points
down
and
the
melting
points
of
the
halogens
group.
DID
3
At
room
temperature
bromine
is
a
liquid
fluorine
and
and
iodine
is
a
chlorine
are
Fluorine
solid.
all
4
Displacement
reactions
involve
the
replacement
of
one
ion
by
the
has
The
A
reactivity
more
of
the
halogens
decreases
down
the
group.
reactive
halide
halogen
displaces
a
less
reactive
one
The
solution
oxidising
easier
stronger
oxidant
This
is
of
small
because
atom
because
the
more
reactive
halogen
it
the
is
electron
with
shells.
electron
An
entering
experiences
its
nearly
the
from
has
force
of
the
positive
nuclear
a
An
iodine
atom
has
five
power.
electron
7
a
shell
charge.
greater
best
halogens.
additional
full
a
the
such
two
outer
6
is
another.
only
5
KNOW?
atom
it
or
YOU
gases,
for
a
halogen
oxidising
power
atom
of
to
the
accept
an
halogen.
electron,
the
the
shells
nuclear
nucleus
is
and
charge
well
even
is
though
higher
the
screened.
33
4.4
LEARNING
At
the
should


end
be
explain
the
trends
Trends
of
OUTCOMES
of
this
able
topic
you
to:
periodicity
describe
Periodic
trends
periodic
As
in
Period
3
of
predict
properties
move
the
is
the
3
left
properties
marked
and
to
of
in
occurrence
the
the
the
right
in
the
elements
others
of
periodic
there
similar
is
table
periodic
change.
a
In
gradual
properties
of
table,
some
change.
the
the
physical
instances
the
Periodicity
elements
in
the
of
elements
based
position
of
the
the
periodic
table.
table
so
that
elements
in
a
given
group
have
similar
properties
on
or
the
element
a
trend
in
properties.
T
able
4.4.1
shows
some
of
these
trends.
in
T
able
Electron
from
regular
periodic
unknown
Period
chemical
change
table
is

we
and
in
4.4.1
Properties
across
Period
Na
Mg
Al
Si
P
2,8,1
2,8,2
2,8,3
2,8,4
2,8,5
3
S
Cl
2,8,6
Ar
2,8,7
2,8,8
arrangement
−
−
−
−
Electron
1e
2e
3e
4e
gain
loss
loss
loss
no
(on
or
loss
−
ions
−
−
3e
2e
1e
no
gain
gain
gain
or
loss
gain
formed,
forming
electrons
ions)
shared
State
at
solid
solid
solid
solid
solid
solid
gas
gas
883
1107
2467
2355
280
445
−35
−186
conductor
conductor
conductor
semiconductor
insulator
insulator
insulator
insulator
metal
metal
metal
metalloid
non-
non-
non-
non-
metal
metal
metal
metal
25 ºC
Boiling
point
(ºC)
Electrical
conductivity
Metal
or
non-metal

EXAM
charge
fo rm
ed
grou
p
or
the
on
from
gene
rally
the
an
equa
l
num
ber
grou
p
ion
atom
to
fo r
is
the

me ta
ls
So
II
8
fo rm
s
non -m
e tals
.
the
ion
in
conduct
deriv
ed
nitri
de
from
V
electricity
metals
have
some
Across
the
to
but
metalloids
period
the
Metals
non-metallic
the
non-metals
lying
properties
different
tend
at
to
the
Group
0)
character
across
the
of
boiling
both
point
structures
of
do
between
metals
increases
the
not.
the
and
and
are
non-
non-metals.
then
elements
Non-metals
metals
decreases.
(see
This
5.4–5.6).
Across
the
lose
electrons
right-hand
tend
to
gain
in
side
forming
of
the
ions,
table
whereas
(apart
from
the
non-
elements
in
electrons.
2+
period
the
ability
of
the
atoms
to
lose
electrons
ion
and
their
ability
to
gain
electrons
increases.
in
There
are
also
periodic
changes
in
chemical
properties
and
reactivity
N
across
outer
the
shell
reaction
34
metallic
Mg
nitro
gen
3–
is
in
The
decreases
Grou
p
change
insulators.
metals
Grou
p

the
a
num
ber
fo r
mag
nesium
and
Metals
reflects

minus
is
period.
TIP

T
he
There
period.
The
electrons
with
water:
in
chemical
the
properties
atoms
of
the
depend
element.
on
For
the
number
example,
in
of
the

sodium
reacts

magnesium

aluminium
very
rapidly
and
forms
an
alkaline
solution
DID
reacts
very
slowly
and
forms
a
slightly
alkaline
YOU
KNOW?
solution
Mendeleev
only
reacts
slowly
when
heated
in
periodic

silicon,
phosphorus

chlorine
and
sulfur
do
not
to
form
an
acidic
table
solution.
thought
and
the
properties
of
unknown
their
can
use
properties
the
of
trends
elements
in
the
that
properties
we
know
of
little
He
of
elements
to
deduce
the
about.
the
the
1
their
data
below
to
deduce
the
state
and
not
yet
studied
adjacent
the
been
the
elements
and
boiling
point
of
properties
undiscovered
When
be
Use
his
elements
gallium,
germanium
Example
in
elements
compounds
predicted
We
had
discovered.
properties
Deducing
spaces
for
react
he
reacts
left
steam
scandium
were
properties
very
close
of
elements.
were
to
and
discovered,
found
to
Mendeleev’s
astatine
predictions.
and
whether
T
able
or
4.4.2
not
Data
iodine
about
will
State
Chlorine
Gas
Bromine
Liquid
Iodine
Solid
Astatine
?
is

Astatine

Its
below
iodine
should
be
a
with
potassium
astatide.
halogens
Halogen
Astatine
react
at
25 ºC
Boiling
point
point
O
F
Si
P
S
Cl
Ge
As
Se
Br
Sn
Sb
Te
I
+59
+184
Figure
Group
VII.
So
continuing
the
trend:
KEY
4.4.1
POINTS
solid.
1
melting
N
–35
?
in
C
(ºC)
should
be
above
+184 ºC.
The
difference
Periodicity
is
occurrence
melting
point
between
chlorine
and
bromine
is
94 ºC
and
bromine
and
iodine
is
125 ºC.
So
continuing
the
estimate
astatine’s
boiling
point
by
adding
a
value
of
The
estimated
value
is
then
184
+
150
=
334 ºC
=
Across
elements
in
a
period
from
there
metals
is
on
a
the
337 ºC).
left

the
table.
(actual
change
value
of
periodic
perhaps
2
150 ºC.
regular
similar
increase,
the
we
of
that
properties
between
the
in
Potassium
astatide
will
react
with
iodine
to
form
potassium
to
non-metals
on
the
iodide
right.
and
astatine.
halogen
This
(iodine)
follows
will
the
react
pattern
with
the
that
halide
the
of
more
the
reactive
less
reactive
3
The
the
halogen.
in
Example
of
the
periodic
your
elements
properties
table
of
shown
selenium
in
Figure
(Se)
from
its
position
in
the
knowledge
around
it,
of
the
Metals
is
a

does

forms
between
non-metals
table.
non-metal
in
section
periodic
table
by
looking
at
As
we
the
the
VI
of
the
periodic
go
are
electricity
but
insulators.
across
ability
lose
selenium:
Group
conduct
4.4.1.
their

periodic
non-metals
5
Using
the
are
and
2
4
Predict
metalloids
metals
of
the
electrons
ability
to
a
period,
atoms
to
decreases
gain
and
electrons
table
increases.
not
conduct
electricity
(is
an
insulator)
6
Trends
in
the
properties
2−

is
a
ions
solid
of
at
type
room
Se
(since
it
temperature
is
in
since
Group
S
is
VI)
also
a
of
elements
to
deduce
of
elements
can
be
used
solid.
little
the
properties
that
we
know
about.
35
5
Structure
5.1
and
bonding
Ionic
bonding
The
LEARNING

At
the
end
formation
of
this
topic
be
ions
Positive
able
ions
are
formed
when
an
atom
the
formation
draw
Negative
ions
dot-and-cross
For
→
Mg
−
+
2e
are
formed
when
an
atom
gains
one
or
more
example:
diagrams
−
O
to
electrons.
bonds
electrons.

more
of

ionic
or
to:
2+
describe
one
example:
Mg

loses
you
For
should
of
OUTCOMES
show
ionic
+
2−
2e
→
O
bonding.

The
charge
on
the
ion
depends
on
the
number
of
electrons
lost
or
gained.

For
most
metal
ions
the
number
of
positive
charges
is
the
same
as
the
3+
group

For
number
.
most
group
For
example,
non-metal
number.
For
ions,
aluminium
the
example,
is
negative
in
Group
charge
phosphorus
is
in
is
III,
so
eight
Group
its
ion
minus
V
,
so
is
Al
.
the
the
3−
phosphide
DID
YOU
Some
non-metals
can
is
P
.
form
Forming
positive
ion
KNOW?
ions.
The
hydrogen
the
noble
gas
configuration
ion,
+
H
is
the
Some
charged
a
best
metals
ions.
negative
of
known
can
Sodium
ion
sodium
in
with

example.
form

ethers,
metals
of
metal
forms
compounds
crown
When
shell
negatively
Each
the
combine
metal
with
atoms
non-metals,
are
transferred
the
electrons
completely
in
to
the
the
outer
non-
atoms.
non-metal
atom
usually
gains
enough
electrons
to
fill
its
outer
shell.
+
which
ions
contain
and
Na
crown
ether–Na

Each

The
metal
atom
ions
formed
arrangement

The
strong
results
EXAM
TIP
For

Rem
embe
r:
in
The
In
most
of
that
you
me ta
l
be
there
chlorine
shell
electrons.
and
noble
attraction
bond
5.1.1
atom
of
nearest
of
ionic
metal
has
(see
gas
one
for
the
more
up
gas
with
the
electron
configuration).
oppositely
charged
ions
details).
that:
electron.
The
ion
has
the
electron
neon.
ion
atom
has
has
the
gained
electron
the
electron
arrangement
in
The
argon.
×
the
Cl
××
Na
Na
Cl
hydr
ide
××
there
of
sodium.
+
××
the
from
××
××
in
end
(noble
between
5.4
shows
lost
non-metal)
×
will
××
be
+
electro
ns
in
2,8,1
2,8,7
[2,8]
shell
.
[2,8,8]
+
NaCl
Figure
5.1.1
The
ions
36
outer
××
two
outer
the
Figure
sodium
chloride
will
−
,
its
non -
shell
.
H
only
the
fo r
electro
ns
Howe
ver
,
ion,
draw
The
××

struct
ures
ions,
eigh t
outer
loses
the

electro
nic
(both
force
an
example,
of
arrangement

usually
ions.
sodium
formed
atom
have
transfers
the
its
electron
outer
( Na
electron
arrangement
to
of
a
Cl
)
chlorine
the
nearest
atom,
noble
so
both
gas.
Dot-and-cross
Dot-and-cross
electrons
cross
have
the
outer

the
charge
diagrams
come
diagrams

diagrams
from
help
+
us
when
an
to
keep
ionic
track
bond
of
is
where
formed.
the
Dot-and-
Cl
Na
show:
electron
shells
only
Figure
of
×
the
ion
at
the
top
right
outside
square
5.1.2
Dot-and-cross
sodium
Figure
5.1.2
Examples
shows
of
the
dot-and-cross
dot-and-cross
diagram
diagrams
for
for
sodium
ions
TIP
oxide
When
The
two
electrons
in
the
outer
shell
of
the
magnesium
atom
draw
ing
to
the
outer
shell
of
the
oxygen
atom.
Each
ion
has
arrangement
of
the
nearest
noble
gas
(Figure
diag
rams
the
ionic
electron
struct
ures,
5.1.3).
sure
of
+
2
that
the
the
ion
bracke
ts
Mg
O
no t
put
centre
the
2+
2,8,2
2,6
2–
[2,8]
ion.
Do
in
It
charge
the
is
charge
.
bracke
ts
the
to p
no t
T
he
show
is
sprea
d
5.1.3
even
ly
Calcium
over
the
ion.
chloride
calcium
has
chlorine
atom
only
atoms
loses
space
are
in
its
its
two
outer
outer
needed
to
shell
react
electrons.
for
with
one
one
A
single
electron.
calcium
chlorine
So,
two
atom.
Each
of
KEY
the
the
charge
nucle
ar
that
atom
outsid
e
at
co rn
er
.
the
[2,8]
MgO
The
the
of
squa
re
Figure
charge
goes
righ t-h
and
O
of
mak
e
2
–
the
Mg
do t-
are
andcross
transferred
for
chloride
chloride.
EXAM
Magnesium
diagram
brackets.
chlorine
atoms
gains
one
electron
(Figure
POINTS
5.1.4).
1
Metal
ions
charged
loss
2
of
are
and
positively
are
formed
by
electrons.
Non-metal
ions
are
Cl
Cl
negatively
charged
and
are
+
2
formed
[2,8,8]
2,8,7
Ca
3
Most
by
ions
gain
of
have
electrons.
the
noble
Ca
gas
4
Cl
electron
Ionic
bonding
complete
Cl
arrangement.
involves
transfer
of
the
one
or
+
2
2,8,7
more
electrons
atom
to
a
from
non-metal
a
metal
atom.
[2,8,8]
5
Dot-and-cross
diagrams
CaCl
2
for
Figure
ions
show
the
electron
5.1.4
arrangement
of
and
ions
or
negative
crosses
origin
of
to
the
the
positive
using
represent
dots
the
electrons.
37
5.2
Covalent
What
LEARNING
the
end
of
this
topic

be
When
able
the
covalent
bonds
formation
dot-and-cross
show
or
more
non-metals
combine
they
share
one
or
more
electrons.

A
shared

The
covalent
pair
of
electrons
is
called
a
covalent
bond
of
shared
shell
electrons
of
the
in
the
atoms
covalent
that
bond
usually
arise
from
the
combine.
diagrams

to
bond?
to:
describe
draw
two
of
outer

covalent
you
pairs
should
a
OUTCOMES

At
is
bonding
When
some
non-metal
atoms
combine,
not
all
the
electrons
in
the
bonding.
outer
shell
covalent

In
form
covalent
bonding
writing
are
displayed
bonds.
called
The
lone
formulae,
a
pairs
of
electrons
not
used
in
pairs
single
covalent
bond
is
shown
as
a
××
single
line
between
the
atoms,
Cl − Cl.
e.g.
×
××
Cl
Cl
Drawing
To
draw
a
dot-and-cross
dot-and-cross
diagrams
diagram
for
a
for
molecules
molecule:
××

Use
a
dot
electrons
Covalent

If
there
other
×
××
Cl
The
outer

The
electrons
In
a
of
one
(see
of
the
Figure
atoms
and
a
cross
for
the
5.2.1).
than
such
electrons
of
gas
are
outer
as
two
a
are
so
in
Some
atom,
or
we
can
give
the
electrons
square.
pairs.
that,
electrons
configuration.
of
circle
drawn
arranged
shell
types
small
if
that
of
possible,
each
corresponds
these
to
electrons
atom
the
will
has
the
nearest
be
shared
pair
and
5.2.1
other
more

noble
Figure
are
symbols
number
××
Lone
electrons
the
bond
××
Cl
for
of
chlorine
each
atom
electrons,
covalent
other
may
not
be
shared.
molecule,
shares
a
forming
pair
a
of
Figure
5.2.2
shows
how
we
draw
a
dot-and-cross
diagram
for
methane.
single
bond.
×
H
H
×
YOU
KNOW?
×
H
×
DID
few
the
noble
covalent
atoms
gas
molecules,
may
not
electron
have
C
+
one
the
H
a
C
H
of
×
In
×
H
×
arrangement.
H
An
example
is
boron
trichloride,
×
H
where
the
boron
atom
has
Carbon
atom
only
(2,4)
Methane
six
electrons
around
it.
4
are
called
molecule
These
hydrogen
Each
atoms
hydrogen
shares
electron-deficient
two
(1)
electrons
with
carbon
molecules.
Figure
5.2.2
Molecules
38
with
Figure
5.2.3
water,
ammonia
only
shows
single
bonds
dot-and-cross
and
ethane.
diagrams
for
hydrogen
chloride,
a
a
H
Cl
×
×
+
×
H
Cl
O
O
×
Oxygen
Hydrogen
atom
Chlorine
atom
Hydrogen
molecule
chloride
b
(1)
(2,8,7)
molecule
×
b
pairs
×
×
Lone
×
N
×
N
×
H
H
O
×
+
O
Nitrogen
molecule
×
H
×
c
atom
C
×
O
Water
(2,6)
×
Oxygen
atoms
O
hydrogen
×
2
×
H
molecule
(1)
c
Carbon
Lone
molecule
d
H
×
H
H
dioxide
pair
×
C
H
N
×
×
H
3
C
H
H
N
H
+
×
×
H
Ethene
H
hydrogen
Nitrogen
atom
Ammonia
molecule
Figure
atoms
molecule
5.2.4
(2,5)
(1)
d
KEY
×
H
C
1
H
H
×
H
×
×
+
C
H
H
A
covalent
C
sharing
a
each
which
of
a
When
atoms
usually
hydrogen
2
carbon
atoms
atoms
pair
of
electrons,
originates
different
covalent
6
by
atom.
combine
to
form
H
H
×
H
formed
×
2
C
×
is
H
from
×
H
bond
×
×
×
×
H
POINTS
Ethane
molecule
bonds,
has
around
its
each
eight
outer
atom
electrons
shell,
except
(2,4)
for
hydrogen,
which
has
two.
(1)
3
Figure
A
single
shown
5.2.3
covalent
as
a
line
bond
is
between
the
atoms.
Molecules
with
multiple
bonds
4
Some
atoms
double
the
are
bond.
able
We
dot-and-cross
atom
(2,6)
needs
to
can
share
show
diagram
to
gain
two
this
for
two
an
pairs
by
a
of
electrons.
double
oxygen
electrons
line.
call
When
molecule,
to
We
each
complete
its
this
a
drawing
only
do
this
by
sharing
two
pairs
of
electrons.
A
double
bond
formed
When
a
three
triple
pairs
bond
of
is
electrons
formed.
are
Figure
shared,
5.2.4
as
in
shows
the
A
triple
for
oxygen,
nitrogen,
carbon
dioxide
and
two
pairs
shared
atoms.
covalent
when
bond
three
is
pairs
nitrogen
electrons
are
shared
dot-and-cross
between
diagrams
are
bond
two
is
of
molecule,
when
It
formed
formed.
covalent
electrons
between
shell.
5
can
double
is
of
oxygen
outer
A
two
atoms.
ethene.
39
5.3
Ions,
molecules
formula
Ionic
LEARNING
the
end
of
this
topic
be
Compounds
able
II
predict
an
the
atom
likelihood
forming
covalent
ionic
write
are
with
likely
a
to
be
reactive
ionic
when
non-metal
a
reactive
near
the
metal
top
of
in
Group
Group
VI
I
or
accept
or
is
because
elements
Group
near
the
I
top
and
of
II
elements
Groups
VI
readily
and
VII
lose
electrons
generally
readily
electrons.
bonds
formulae
ions,
This
and
of


reacts
to:
VII.

covalent?
you
or
should
units
OUTCOMES

At
or
and
to
molecules
and
Compounds
This
represent
is
similar.
formula
So
transfer
units.
Three

A
are
because
likely
the
neither
it
to
of
the
completely
types
of
molecular
particular
be
power
covalent
of
the
atoms
and
chemical
formula
element
in
gives
one
can
make
when
atoms
an
to
two
non-metals
attract
attract
an
the
react.
electrons
electron
is
enough
to
ion.
formula
the
number
molecule
of
a
of
atoms
of
compound,
each
e.g.
HBr,
Cl
,
2
H
O,
C
2

H
H
−
CH
H
OH
−
C
−
C
−
2
−
O
except
−
H
how
structural
Displayed
formula

An
of
5.3.1
Simplified
for
the
formula
and
formula
of
ethane,
and
are
C
in
H
2
to
their
(see
ordered
power
electrons.
The
of
of
an
is
covalently
ionic
5.4)
,
a
In
bonded
of
to
attract
electrons
a
not
an
The
displayed
Figure
called
is
its
a
difference
gives
the
is
CH
6
simplest
For
whole
example,
atoms,
be
the
in
between
compound
covalent.
difference
If
in
For
may
character
the
there
some
the
bonding

For
is
is
a
8
the
likely
to
compounds
have
formula
MgCl
the
40
of
formula
,
unit
Na
ionic
compounds
thousands
for
an
ionic
of
positive
and
compound
is
negative
the
ions
empirical
O.
2
of
positive
charges
is
balanced
by
the
number
of
charges.
metal
ions
same
in
as
Groups
the
group
I,
II
and
III,
number,
the
e.g.
positive
Na
charge
2+
,
Ba
,
on
the
ion
3+
Al
non-metal
the
ions
group
in
Groups
number,
V
,
VI
e.g.
Cl
and
,
S
VII,
the
negative
charge
is
3−
,
N
+
The

The
hydrogen
ion
is
H
larger
charges
of
to
bottom
of
of
transition
Groups
IV
element
and
V
ions
may
and
vary
elements
and
have
towards
to
be
learnt
ionic
bond
pair
nearer
other
.
ratio
compound:
number
minus

separately
(see
Subscripts
are
electrons
one
T
able
5.3.1).
because
atom
used
to
show
the
number
of
atoms
combining,
e.g.
is
in
pulled
number
empirical
If
the

the
show
electronegativity,
be
in
formulae
.
for
e.g.
ionic
the
the
there
a
3
2−
electronegativity
in
bonds
itself
electronegativity.
small
any
5.3.1).
+
there
bonded
bonding
towards
is
is
are
show
to

pair
(see
compound.
formulae
the
negative
another
but
atoms
do
atom

that
the
according
attracting
ability
bonds
arranged
2
be
triple
how
formulae
displayed
KNOW?
can
us
ethanol
formula,
Atoms
shows
structural
formula
ions
structural
Since
YOU
bonds
or
Writing
DID
double
empirical
atoms
formula
Figure
formula
Simplified
H
H
Simplified
6
structural
−
3
2
O.
molecule.
−
CH
A
H
than
P
O
4
,
6
there
are
four
phosphorus
atoms
and
six
oxygen
atoms.
T
able
5.3.1
Singly
The
charge
charged
on
some
Doubly
charged
+
Silver,
ions
Triply
charged
2+
Ag
Iron(II),
EXAM
TIP
3+
Fe
Iron(III),
Fe
Alth
ough
+
Copper( ),
the
2+
Cu
Copper(II),
fo rm
Cu
of
ionic
ulae
compo
unds
look
2+
Zinc,
Zn
like
mo lec
ular
fo rm
ulae,
2+
Lead(II),
we
Pb
cann
ot
‘mo lec
ular
We
can
deduce
the
formula
for
magnesium
bromide
as
2+
Write
down

Balance

Write
the
ions
separately:
Mg
and
the
term
fo rm
ula’
fo r
follows:
them
.

use
We
‘fo rm
ula
Br
use
the
unit’
term
instea
d.
2+
the
the
charges:
formula
we
with
need
the
two
metal
Br
to
ion
balance
first:
one
Mg
MgBr
2
Some
ions
contain
more
than
one
type
+
of
atom:
2−
NH
OH
NO
4
ammonium
hydroxide
2−
SO
3
CO
4
nitrate
HCO
3
sulfate
3
carbonate
hydrogencarbonate
EXAM
The
formulae
same
way
shown
in
by
of
compounds
balancing
Figure
the
containing
charges
of
these
the
ions
ions.
are
T
wo
found
in
examples
Bein
g
are
5.3.2.
is
nitrate
Sodium
present
sulfate
+
3+
one
numbers
Mak
e
to
ions
3+
balance
the
3 × NO
2 × Na
3
Figure
formulae
formulae
oxidation
for
for
Na
sure
the
that
you
charge
s
the
on
the
combi
ning
rs
of
atom
s.
SO
2
3
covalent
compounds
numbers
combining
4
powers
(see
of
8.1).
can
As
different
a
often
be
rough
atoms
compounds
found
guide
(T
able
from
we
can
knowledge
use
the
of
idea
T
able
5.3.2
The
combining
non-metal
of
power
of
atoms
5.3.2).
Atom
Combining
power
So:
Carbon,

to
5.3.2
Writing
The
keys
chem
istry
.
4
)
3
the
1 × SO
powe
Al(NO
write
compo
unds
the
in
and
2–
+
1 × Al
charges
to
of
2
4
know
the
of
succ
ess
Na
Al
3
Swap
able
fo rm
ulae
Aluminium
Ions
TIP
the
one
C
atom
combines
with
four
H
atoms
in
methane,
C
4
CH
4

two
atoms
dioxide,
of
oxygen
combine
with
one
atom
of
carbon
in
carbon
CO
Chlorine,
Cl
Hydrogen,
H
1
1
2

one
KEY
1
atom
of
H
with
one
atom
of
Cl
to
form
HCl.
Oxygen,
O
2
POINTS
Ionic
bonds
reactive
2
When
3
The
The
are
generally
formed
between
reactive
metals
and
non-metals.
non-metallic
formula
balancing
4
combines
formula
combining
of
the
of
an
atoms
ionic
charges
a
compound
on
covalent
powers
combine,
the
covalent
can
positive
compound
(oxidation
can
numbers)
be
and
are
deduced
negative
be
to
bonds
found
each
formed.
by
ions.
by
assigning
atom.
41
5.4
Ionic
compounds:
structure
and
properties
Ionic
LEARNING
The
At
the
end
crystals
OUTCOMES
of
this
topic
regular
particles
should
be
able
describe
in
ionic
or
usually
crystals
draw
a
diagram
arrangement
of
of
describe
the
solids
properties
water
due
to
the
repeating
regular
packing
arrangement
of
of
the
ions,
is
called
three-dimensional
ions.
This
is
a
crystal
lattice.
arrangement
sometimes
called
a
of
In
ionic
lattices
alternating
giant
ionic
there
positive
is
and
structure.
an
ionic
lattice:
the
electrostatic
in
terms
points,
of
and
hardness
act
in
all
forces
between
the
positive
and
negative
directions
their
solubility
organic
and
attractive
of

melting
is
in
ions
ionic
crystal
regularly
chloride


a
A
the
ions
In
sodium
of
crystal.
molecules
a
negative

the
to:
atoms

structure
you
these
forces
are
very
strong.
It
takes
a
lot
of
energy
to
overcome
them.
in
solvents,
The
electrical
structure
Figure
of
5.4.1.
part
You
of
can
a
lattice
see
that
of
the
sodium
ions
are
chloride,
packed
NaCl,
closely
is
shown
in
together.
conductivity

relate
the
structure
of
sodium
a
chloride
to
its
properties
Strong
ionic
b
bonds
and
between
oppositely
uses.
charged
−
+
EXAM
ions
−
+
+
−
−
+
rams
struct
ures
ions
do
covalen
t
of
of ten
that
no t
show
by
Figure
are
no t
Properties
direc
tiona
l.

They
by
have
melt
the
They
are
similarly
forces

ions
shape
are
lattice.
packing
the
of
the
arrangement
ionic
They
are
of
these
shows
the
arranged
ionic
their
high
the
–
ions
of
in
the
sodium
chloride,
b
exploded
view
ions
compounds
structure
melting
large
It
compounds,
and
a
lot
of
of
as
sodium
chloride,
can
be
bonding:
points.
numbers
needs
such
There
are
positive
energy
strong
and
to
attractive
negative
overcome
ions
these
forces
acting
forces
in
to
solid.
brittle.
as
the
The
the
hard.
the
crystals
layers
charged
cause
because
crystals
close
show
of
directions.
direction
The
The
of
properties
explained
all
42
+
Na
Ionic
between
5.4.2
a
lines
.

Fig
–
+
these
repres
ent
bond
s.
5.4.1
to
The
fo rces
–
ionic
joine
d
Rem
embe
r
lines
+
–
Cl
+
the
+
TIP
−
Diag
–
−
+
ions
of
come
crystal
It
takes
strong
to
a
split
ions.
apart
When
close
to
when
the
hit
layers
each
in
the
move
other.
The
same
slightly,
large
repulsive
split.
lot
of
attractive
energy
forces
to
keep
scratch
the
the
ions
surface.
This
is
together.
salt
way
in
the
the

They
are
soluble
molecules
crystal.
form
The
in
water.
weak
forces
When
bonds
between
added
with
the
the
ions
to
ions
water,
on
within
the
the
the
water
surface
crystal
are
of
the
weakened
and
the
ions
eventually
become
surrounded
by
water
molecules.
DID
The
total
ions
and
are
forces
of
greater
negative
attraction
than
ions.
the
So
between
forces
the
of
crystal
the
water
attraction
dissolves
molecules
between
(see
Figure
the
and
YOU
positive
There
the
5.4.3).
are
ions
packed.

They
do
either
ions
not
dissolve
bonds
or
the
are
in
not
bonds
non-polar
formed
are
too
organic
between
solvents
the
(see
organic
5.6)
solvent
They
ions
do
not
are
conduct
not
electricity
free
there
to
In
electricity
be
and
chloride
is
This
is
For
a
when
a
solid.
substance
movement
molten
because
sodium
the
sodium
the
spaces
of
This
to
is
be
because
in
can
which
be
chloride,
ions
fit
well
between
into
the
able
charged
to
or
dissolved
in
water,
does
the
ions
are
free
to
as
close
as
that
larger
they
In
other
possible
to
are
them.
compounds,
such
When
caesium
chloride
and
zinc
conduct
the
way
the
atoms
are
move.
arranged
a
so
conduct
particles.
it
ions
the
sulfide,
electricity.
ways
lattice
the
as
sodium
a
weak.
move.
must
several
in
because
chloride

KNOW?
the
is
different.
b
–
Bond
–
weakens
−
O
−
+
H
H
+
–
+
–
+
–
+
–
+
H
−
−
O
H
–
EXAM
Bond
forms
Represents
a
water
When
Fig
5.4.3
a
Water
molecules
form
weak
bonds
with
the
ions
in
the
In
a
solution,
the
ions
are
surrounded
by
water
aske
d
molecules.
disso
lved
chlor
ide
of
ionic
compounds
that
The

solubility
sodium
manufacturing
aqueous

of
chloride
chlorine
and
makes
sodium
it
useful
for:
hydroxide
by
is
electrolysis
of
its
on
the
rather
roads
in
cold
countries
to
reduce
the
formation
of
ice.
error
o ther
The
high
oxide,
KEY
1
point
them
of
ionic
useful
for
ionic
crystals,
the
positive
Ionic
compounds
have
3
Ionic
compounds
are
polar
5
such
as
is
a
o ther
comm
on
to
nam
e
parti
cles.
magnesium
linings.
and
negative
ions
are
arranged
in
lattice.
2
4
compounds,
furnace
any
exam
s
it
move,
POINTS
In
a
melting
makes
It
sure
that
that
than
in
mak
e
state
ions
parti
cles.
solution
spreading
you
mo lte
n
sodium
cond
ucts
electric
ity,
Uses
why
crystal.
or
b
TIP
molecule
organic
compounds
state
but
An
aqueous
production
roads
in
do
conduct
solution
of
cold
melting
soluble
in
and
water
boiling
but
points.
insoluble
in
non-
solvents.
Ionic
do
high
not
conduct
when
of
sodium
molten
sodium
to
or
reduce
and
the
when
dissolved
chloride
hydroxide
countries
electricity
(brine)
chlorine.
in
is
It
formation
in
the
solid
water.
used
is
of
in
the
spread
ice
on
on
road
surfaces.
43
5.5
Simple
and
molecular
giant
molecular
structures
Simple
LEARNING
Iodine
At
the
end
of
this
topic
be
able
and
describe
simple
and
giant

a
diagram
properties
They
have
of
of
and
describe
of
simple
giant
in
the
atoms

and
are
forces
They
are
relate
the
diamond
their

water
the
and

hardness
structure
and
are
not
stronger
of

They
do
because
the
5.5.1
can
lattice
form
(see
be
related
to
their
structure:
need
the
forces
much
between
energy
to
the
overcome
molecules.
scratched,
it
does
between
in
easily
non-polar
not
the
water
bonds
organic
molecules
those
take
much
energy
to
molecules.
because
with
the
the
in
conduct
have
that
water
the
the
water
molecules
molecules
to
separate
(or
(or
the
sulfur)
molecular
forces
sulfur)
molecules
molecules
crystals,
such
as
5.6).
when
ions
because
iodine
iodine
some
(see
electricity
neither
solvents
and
between
though,
soluble
they
in
enough
solvent
Note,
not
molecular
nor
solid
or
electrons
molten.
that
This
can
is
move.
structures
made
crystalline
or
Part
of
an
iodine
lattice
to
be
with
at
YOU
The
able
In
bonded
to
dissolve
they
bond
hydrogen
carbon
centre
the
of
are
each
the
Each
of
in
both
forms
carbon
the
layers
diamond
whole
of
molecular
Different
are
called
four
atom
network
network
giant
5.5.2).
element
atom
The
throughout
arranged
are
Figure
same
carbon
atoms.
properties
three-dimensional
(see
tetrahedron.
unbroken
atoms
in
a
of
a
graphite
atoms
forms
diamond,
have
and
can
of
covalent
be
imagined
tetrahedrons
structure.
In
hexagons.
and
graphite
properties
of
diamond
and
graphite
can
be
explained
by
their
molecular
containing
to
because
carbon
molecular
almost
structure
nitrogen
Diamond
KNOW?
simple
structures
of
other
the
structures
structures
bonds.
Similarities
44
can
because
not
the
forces
molecular
graphite,
of
a
other.
than
are
covalent
extends
type
They
in
allotropy.
bonds
is
weak
strong
the
allotropes.
are
does
separate
When
each
dissolve
sucrose,
of
Many
sulfur
points
It
dissolve
form
themselves.
to
uses
meaning
They
Giant
DID
and
melting
and
the
from
Giant
Figure
iodine
weak.
soft.
between
of
graphite
and
do
them
conductivity
properties
describe
term
in
They
cannot
melting
solvents,
electrical

and
structures
their
solubility
organic
arranged
properties
molecules
of
structure.
regularly
in
graphite
molecular
terms
points,

the
of
low
overcome

molecular
are
the
these
arrangement
diamond
simple
5.5.1).
molecules
draw
a
molecules
molecular
crystals

have
the
molecular
The
crystals
sulfur
because
to:
Figure

crystals
you
crystals
should
molecular
OUTCOMES
bond.
water
.
a

called
a
They
have
down
This
particular
water
bonding:
or
hydrogen
in
form
with
oxygen
and

They
of
the
are
high
insoluble
covalent
strong
melting
network
bonds
enough
of
in
is
points.
strong
water
too
bonds
and
strong
with
It
needs
covalent
the
in
to
a
lot
of
energy
to
break
bonds.
organic
allow
solvents.
solvent
individual
The
network
molecules
atoms.
to
form
a
Carbon
b
atoms
Strong
bonds
within
layers
EXAM
TIP
Rem
embe
r
Dashed
lines
red
show
be tw
een
that
the
a
a
tetrahedron
Weak
mo lec
ule
are
becaus
layers
bond
s
e
they
but
be tw
een
are
the
the
fo rces
in
strong
forces
between
the
atom
s
covalen
t
fo rces
mo lec
ules
are
weak
.
Figure
5.5.2
a
a
Differences
in
Diamond
layered
has
atoms
arranged
in
tetrahedral
form.
b
Graphite
has
structure.
properties
of
diamond
and
graphite
Hardness:

Diamond
difficult
hardest
of

Graphite
as
Electrical

The
a
no
in
to
each
strong
the
known.
The
layers
layers
as
lubricant
of
This
drilling
forces
can
of
covalent
surface
in
makes
bits
over
the
bonding
crystal.
it
and
between
slide
graphite
and
the
flake
ideal
glass
the
each
of
to
use
is
makes
one
for
the
of
it
the
edges
cutters.
layers
other
away
‘leads’
throughout
Diamond
of
graphite
when
easily
a
and
are
force
so
is
graphite
is
pencils.
conduction:
does
ions.
Graphite
shell
the
such
soft.
the
Diamond
with
tools
is
So
applied.
used
hard:
scratch
substances
cutting
weak.

is
to
not
conduct
There
conducts
use
in
atom
are
electricity.
electrons
electricity.
bonding.
are
no
used
In
to
Carbon
graphite,
form
It
is
free
has
covalent
compound
move.
four
three
covalent
a
to
of
electrons
the
bonds.
in
carbon
The
its
outer
electrons
fourth
Figure
5.5.3
Diamonds
network
electron
in
each
atom
is
free
to
move
around
and
along
the
electrons
difference
KEY
is
are
called
applied,
delocalised
these
electrons
electrons.
move
along
When
the
a
Simple
molecules
forces
Simple
have
between
molecular
the
low
melting
molecules
and
are
boiling
weak.
points
They
are
soft.
It
crystals
do
not
conduct
electricity.
is
a
in
organic
solvents.
Others
dissolve
in
Diamond
Diamond
and
graphite
and
are
graphite
examples
have
high
of
giant
melting
Giant
molecular
structures
are
insoluble
in
abou
t
Some
be tw
een
structures.
boiling
points.
aske
d
mo lec
ular
have
high
structure.
both
water
organic
mo lec
ules
Diamond
Diamond
does
is
not
hard
conduct
but
electricity
graphite
is
but
graphite
does.
mo lec
ules.
answ
ers
soft.
bond
s
8
Diamond
9
Graphite
each
is
is
used
used
for
as
a
drill
tips
because
lubricant
it
because
is
its
very
mo lec
ules
hard.
layers
slide
why
gian
t
melt
ing
is
a
and
solvents.
error
struct
ures
T
here
differe
nce
7
the
strong
water.
molecular
and
comm
on
points
.
6
in
TIP
write
when
5
the
because
fo rces
dissolve
4
of
covalent
layers.
to
3
strong
POINTS
the
2
and
potential
EXAM
1
of
hard
because
layers.
bonds
These
are
long-lasting
carbon
big
be tw
een
and
T
he
refer
simpl
e
best
to
be tw
een
gian
t
strong
the
atom
s.
over
other.
45
5.6
Comparing
Metallic
LEARNING
the
end
of
this
topic
atoms
be
able
describe
metallic
relate
the
atoms
properties
of
their
distinguish
between
in
ions.
They
a
lattice
The
are
and
molecular
metallic
closely
together
and
are
regularly
tend
outer
to
lose
electrons
their
outer
are
free
to
electrons
move
and
terms
of
melting
the
attractive
conductivity,
solubility
and
delocalised.
bond
delocalised
is
formed
by
forces
between
electrons
and
the
positive
ions.
Figure
5.6.1
outer
electron
Positive
ions
hardness.
+
+
+
+
EXAM
that
deloc
alised
is
YOU
The
Figure
e.g.
sucrose,
is
solvents
a
and
and
The
the
molecular
dissolve
polar
have
on
strength
the
the
positive

the
size

the
number
a
one
and
other
.
not
of
in
solids,
partial
high
water
.
solvent.
end
of
Many,
Polar
that
polar
a
like
non-polar
.
polar
but
ions
needs
lot
a
They
are
of
the
increases
ion
ions
metal
ions
as:
of
metals
increases
decreases
delocalised
A
dissolve
electrons
can
be
increases.
related
to
their
structure:
molecules.
So
metals
and
of
have
there
the
are
high
delocalised
energy
to
melting
strong
electrons
overcome
points.
attractive
these
In
forces
acting
forces
in
to
metals
with
between
all
melt
the
directions.
the
It
solid.
wires).
(can
This
be
is
shaped
because,
by
hitting)
when
a
and
force
is
ductile
applied,
(can
the
be
layers
charge
over
each
other
(see
Figure
5.6.2).
Metals
are
not
brittle
like
compounds
because
in
metals,
new
attractive
forces
are
formed
are
useful
and
all,
points
malleable
into
the
delocalised
electrons
and
the
atoms
in
the
layers.
rule
Metals
are
metals
react
insoluble
in
both
water
and
organic
solvents
but
many
dissolve
with
water
rather
than
dissolving.
In
metals
that
non-polar
not
react,
the
metallic
bonds
are
too
strong
to
allow
solvent
non-polar
molecules
sucrose
(a
dissolves
(non-polar)
in
water
dissolves
tetrachloromethane
to
form
strong
enough
bonds
with
the
individual
atoms
polar
in
order
to
separate
them
from
each
other.
and
in
(non-polar).

Metals
the
conduct
delocalised
potential
46
between
electrons
electrons.
bonding
on
metal
not
positive
do
iodine
forces
delocalised
that
this
solvents
molecules
molecule)
attractive
of
+
positive
negative
Solvents
charged
solvents
from
‘sea’
+
their

is
the
melting
between
called
metallic
charge
properties
ionic
are
of

slide
on
arises
+
ions.
drawn
molecule
bonding
delocalised
+
cond
uct
not

charge
Metallic
+
KNOW?
simple
Water
5.6.1
struc
ture

Some
+
+
the
electr
ons
meta
llic
move
it
The
DID
+
+
+
Rem
embe
r
that
+
TIP
electr
icity
,
shows
bonding.
Metal’s
a
the
points,
electrical
in
become
throughout
solids
metallic
in
packed
metallic,
the
ionic
are
structure
The

metal
metals
lattice.
to
a
layers.
bonding
positive

in
to:
Metal

in
you
arranged
should
bonding
OUTCOMES
The
At
structures
electricity
electrons
difference
is
when
can
solid
easily
applied.
or
molten.
move
This
through
is
because
them
when
a
KEY
POINTS
Force
1
applied
Metals
have
a
lattice
structure.
New
bonds
2
formed
Metallic
of
Before
bonding
positive
ions
5.6.2
The
layers
bonds
of
are
a
a
lattice
‘sea’
of
After
delocalised
Figure
is
in
metal
soon
atoms
slide
when
a
force
is
applied,
but
new
3
Metals
electrons.
conduct
electricity
formed.
because
of
their
delocalised
electrons.
4
Metals
are
ductile
because
‘atoms’
malleable
can
the
slide
and
layers
over
of
each
other.
Comparing
T
able
5.6.1
metallic
structures
compares
ionic,
5
simple
molecular,
giant
molecular
Metallic,
ionic,
and
giant
molecular
structures
and
can
be
structures.
distinguished
in
T
able
simple
molecular
5.6.1
Properties
of
ionic,
simple
molecular,
giant
molecular
and
physical
by
differences
properties.
metallic
substances
Ionic
Examples
structure
NaCl,
Simple
MgBr
2
molecular
Giant
molecular
structure
structure
I
Carbon,
,
S
2
,
CO
8
of
bonding
Ionic
(strong
between
+
bonds
and
Covalent
–
(strong)
ions)
the
bonds
between
atoms
forces
but
weak
between
the
molecules
High
electrostatic
(strong
attraction
and
–
Low
force
of
between
+
Sn
bonds
Metallic
between
the
(lattice
no
weak
is
exception,
(weak
attraction
forces
of
between
molecules)
atoms,
forces.
Graphite
its
point
Cu,
dioxide
Covalent
weak
Melting
Fe,
structure
2
silicon
T
ype
Metallic
‘ions’
an
of
bonding
of
within
between
layers.
High
(strong
bonding
covalent
throughout
structure)
Most
few,
high
e.g
gallium,
in
organic
water.
in
Non-polar
non-polar
solvents.
e.g.
in
molecules,
iodine,
dissolve
non-polar
but
polar
dissolve
solvents
Generally
in
polar
insoluble
or
non-polar
are
solvents
molecules
in
polar
‘sea’
Those
react
but
a
sodium
(attractive
and
Insoluble
‘sea’
having
bonds
ions)
Soluble
a
electrons)
between
Solubility
metal
and
low
forces
metal
of
that
with
ions
electrons)
do
not
water
are
insoluble
in
water.
Insoluble
in
non-
polar
solvents.
solvents.
Electrical
Solid
conductivity
conduct
does
move).
when
(ions
Does
cannot
Conducts
molten
aqueous
(ions
not
can
or
in
solution
move).
(no
not
conduct
mobile
delocalised
ions
or
electrons).
Does
ions
not
or
conduct
delocalised
electrons).
graphite
the
(no
Exception:
(some
electrons
Conducts
outer
(the
electrons
are
delocalised).
of
are
delocalised).
47
6
The
mole
6.1
concept
Moles
and
molar
masses
Small
LEARNING
The
At
the
end
of
this
topic
formula
be
able
of
a
compound
shows
the
number
of
atoms
of
each
you
type
should
masses
OUTCOMES
present
in
one
molecule
or
one
formula
unit.
In
water:
to:

T
wo
atoms
of
hydrogen
(A
=
1.0)
combine
with
one
atom
of
r

define
the
mole
and
molar
oxygen
(A
=
16.0).
r
mass

state
Avogadro’s

calculate
mass
relative
(or

So
the

This

The
ratio
of
mass
of
hydrogen
to
oxygen
atoms
is
2 : 16.
law
ratio
is
the
same
however
much
water
we
have.
molecular
relative
mass
of
even
1 000 000
molecules
of
water
is
too
small
to
be
formula
weighed.
mass)


distinguish
between
So
we
have
weigh
mass
and
relative
to
scale
up
a
great
deal
more
to
get
an
amount
we
can
molar
accurately.
mass.
Relative
In
3.3
we
molecular
saw
that
the
mass
relative
and
atomic
relative
mass
(A )
formula
was
defined
mass
in
terms
r
of
EXAM
the
Mak
e
the
a
sure
how
atom
s
bracke
ts.
used
,
num
ber
to
a
carbon-12
coun
that
the
When
atom.
molecular
dealing
Values
mass
with
of
A

t
Relative
molecular
compound
in
a
has
bracke
ts
We
mass
find
masses
bo tto
m
multip
lies
inside
Cu(N
the
O
)
3
ion
and
NO
.
2
has
2
of
atom
s
nitra
in
1
=
and
oxyg
en
to tal
2
3
O
of
on
carbon
a
all
mass
scale
exactly
relative
of
=
unit.
2
per
the
on
term
12
is
atoms
dioxide
(CO
relative
an
atom
mass
of
of
the
one
molecule
carbon-12
of
a
isotope
has
units.
molecular
the
the
where
in
)
is
masses
a
by
adding
molecule.
found
So
using
up
the
the
A
the
relative
relative
values
atomic
molecular
C
=
12.0
mass
and
r
16.0:
e.g.
12.0
+
(2
×
16.0)
=
44.0
2+
te
there

compounds
Relative
formula
compound
a
=
ionic
we
use
the
term
relative
formula
mass.
ions,
mass
of
on
mass
a
scale
exactly
12
is
the
relative
where
an
mass
atom
of
of
one
the
formula
carbon-12
unit
of
isotope
a
has
units.
6
We
calculate
molecular
Ca(OH)
is
relative
masses.
found
formula
So
by
the
masses
relative
using
the
A
2
Note
The
A
that
formula
40.0 g
+
relative
mole
mole
in
exactly
formula
values
Ca
=
and
2
×
masses
the
(abbreviation:
mass)
and
a
in
(16.0
of
do
1.0)
not
=
2
×
of
same
way
calcium
40.0,
O
=
as
relative
hydroxide
16.0,
H
=
1.0:
So
is
a
chlorine
the
74.0
have
Avogadro
mol)
grams.
mole
+
any
relative
mole
of
35.5
=
71 g.
units.
constant
mass
calcium
molecules,
Cl
(atomic,
atoms
(A
2
of
the
mass
r
40.0
48
found
use
Cu
nitro
gen
×
atom
s
fo rm
ula
one
is
For
two
So
×
what
bracke
ts,
3
are
be
we
(M ).
2
righ t
can
molecules
r
smal
l
the
table.
you
ions
When
at
periodic
relative
that
or
fo rm
ula
are
of
r
the
know
mass
TIP
=
r
molecular
has
35.5)
a
mass
has
a
or
of
mass

A
mole
is
the
specified
amount
particles
of
substance
(atoms,
that
molecules
or
has
the
ions)
as
same
number
there
are
of
atoms
in
EXAM
exactly

We
12 g
often
mass
of
the
refer
to
carbon-12
the
mass
of
one
mole
of
a
substance
as
its
In
molar
it
(M).
−1

Molar
mass
has
a
unit
of
TIP
isotope.
grams
per
mole
usually
written
as
g mol
writi
ng
is
clear
.
abou
t
impo
rtant
what
mo les
,
to
type
mak
e
of
−1
So
the
molar
mass
of
sodium
is
23.0 g mol
parti
cles
.
to.
23
The
number
atoms.
This
of
atoms
number
in
is
a
mole
called
of
the
atoms
is
very
Avogadro
large:
6
constant
×
For
10
(symbol
L).
So
is
being
exam
ple,
chlor
ine,
Cl
,
is
1 mol
of
sodium
there
are
6
×
10
sodium
atoms:
it

The
mole
is
therefore
the
amount
of
substance
that
is
mo lec
ules
2 mo
l
of
of
1 mo
l
2
chlor
ine
23
in
referr
ed
71 g
of
but
chlor
ine
contains
atom
s.
23
6
×
10
of
Relating
The
the
specified
moles
number
of
to
moles
particles
in
the substance.
mass
of
a
substance
is
easily
found
by
dividing
the
DID
mass
or
of
the
substance
relative
in
grams
molecular
or
mass
number
of
moles
by
the
relative
formula
of
mass
substance
atomic
for
in
mass
for
compounds.
grams
YOU
KNOW?
elements
Amedeo
whom
(g)
=
is
Avogadro,
the
named,
after
Avogadro
was
the
constant
first
to
–1
molar
mass
(g mol
)
suggest
that
a
molecule
was
the
Example
smallest
Deduce
the
number
sodium
hydroxide.
of
(A
moles
of
values:
sodium
Na
=
hydroxide
23.0,
O
(NaOH)
=16.0,
H
=
in
10 g
of
1.0)
could
also
particle
exist
of
a
gas
that
independently.
defined
the
atom
as
He
the
r
Molar
mass
of
NaOH
=
23.0
+
16.0
+
mass
So
number
of
moles
1.0
smallest
indivisible
element
that
=
mass
=
0.25 mol
chemical
NaOH
40
however
,
of
Avogadro’s
Avogadro’s
temperature
same
of
all
gases
number
of
law
at
states
that
pressure,
of
molecules.
the
moles
same
of
under
equal
the
From
this
temperature
gas.
At
same
volumes
room
it
of
conditions
all
gases
mole
KEY
1
of
an
can
change.
take
work
particles
in
He
part
out
a
did
in
a
the
not,
number
mole.
follows
and
that
pressure
temperature
any
gas
occupies
a
volume
of
equal
contain
and
24 dm
of
contain
the
volumes
the
pressure
3
one
of
law
and
number
particle
40.0
10
=
molar
=
same
(r.t.p.),
3
(1 dm
3
=
1000 cm
).
POINTS
Relative
of
a
molecular
compound
isotope
has
a
mass
on
mass
a
is
the
scale
of
relative
where
exactly
12
an
mass
atom
of
of
one
the
molecule
carbon-12
units.
23
2
The
of
mole
the
is
the
specified
3
Molar
mass
4
Number
is
amount
of
particles
the
mass
in
of
mass
of
moles
substance
that
contains
6
×
10
the substance.
one
of
mole
of
a
substance.
substance
=
molar
mass
Figure
6.1.1
Amedeo
an
5
Avogadro’s
law
states
that
under
the
same
conditions
Avogadro
Italian
deduced
temperature
and
pressure,
equal
volumes
of
all
gases
same
number
of
was
who
that
equal
volumes
contain
of
the
scientist
of
gases
contain
equal
molecules.
numbers
of
molecules.
49
6.2
Balancing
The
LEARNING
the
end
of
this
topic
be
law
of
able
balance
of
state
balance

state
of
break
symbol
including
the
use
ionic
the
law
or
of
conservation
a
of
bonds
rearrange
type
of
mass
reaction,
are
made
themselves
atom
states
is
that
equal
to
in
the
a
chemical
mass
of
the
on
each
some
in
so
that
side
of
the
forming
of
there
the
bonds
the
is
in
the
products.
the
same
reactants
The
atoms
number
of
equation.
equations
full
symbol
shorthand
each
use
the
‘ioni
c’
o ppos
ite),
1
it
equa
tion
are
reaction
may
in
be
Write
the
of
H
2
the
Count
the
coloured
dots
are
Balance
2
+
is
showing
a
equal
method
of
is
number
the
balancing
you
chan
ge
the
to
form
water
go
H
products:
O
atoms
→
of
each
element.
You
may
using
H
O
or

atoms
by
+
O
the
putting
count
2

on
products.
Then

In

but
number
this
case
it
only
in
is
1
front
on
of
oxygen
the
one
that
right.
of
needs
again.
→
2H
2

a
left
O
2







4
of
Now
balance
needs
T
he
the
other
the
2H
front
atoms.
In
this
case
it
is
hydrogen
that
balancing:


+

O
→
2H
2


O
2







fo rm
ula.
num
ber
fo rm
ula
in
front
of
multip
lies
The
reaction
Calcium
of
calcium
hydroxide,
hydroxide
Ca(OH)
,
reacts
with
with
nitric
nitric
acid,
acid
HNO
2
the
find
2

atoms
reactants
num
bers
at
and
mus
t
any
ulae.
reactants
2
2
alwa
ys
oxygen
you.
O

H
balanc
ing
way
throug
h
the
calcium
nitrate
Ca(NO
)
3
fo rm
ula,
e.g.
in
are
2C
atom
s.
and
atom
s
1
Write
the
formulae
2
for
the
reactants
and
products:
and
Ca(OH)
+
2
HNO
→
3
,
3
water.
2CH
4
8H
products
and
the
2
of
oxygen
the
balancing.
equa
tions
,
the
→
helps

balanc
ing
fo rm
and
2
number

there
equation)
When
below.
for
O
2
TIPS
When
+
H
the
EXAM
all
molecular
reaction.
oxide.
3
a
examples
a
ionic,
There
T
he
reactants
hydrogen
2

of
T
wo
shown
formulae
(see
thou
gh
mag
nesium
the
the
called
chemical
from
equa
tion
even
compo
unds
no t
in
a
equa
tion
distin
guis
h
e.g.
atom
balanced.
equation
The
the
(sometimes
describing
term
‘mo lec
ular ’
an
of
of
TIP
an
We
is
equation
way
type
equation
EXAM
50
of
products
mass.
of

the
chemical
new
Symbol
a

mass
equations
A
to
mass
In
and
ions
each
symbols

of
to:
molecular
equations
conservation
the
reactants.

conservation
you
reaction,
should
of
OUTCOMES
The
At
law
equations
Ca(NO
)
3
+
2
H
O
2
to
form
2
Count
of
the
atoms
number
such
as
of
atoms
OH,
SO
,
or
CO
4
Ca(OH)
+
HNO
2
1Ca
groups
,
NO
3
1H
→
Ca(NO
)
3
1NO
1Ca
Balance
the
nitrate,
+
Keep
the
individual
H
2
groups
units.
O
2
2NO
3
3
atoms.
their
3
3
2OH
of
as
2H
1O
3
NO
3
Ca(OH)
+
2HNO
2
1Ca
→
Ca(NO
3
2OH
2H
)
3
2NO
1Ca
3
4
Balance
the
hydrogen
Ca(OH)
+
H
O
2
2H
1O
3
and
2HNO
2
+
2
2NO
oxygen.
→
Ca(NO
3
)
3
+
2H
2
O
2
Figure
1Ca
2OH
2H
2NO
1Ca
2NO
3
4H
6.2.1
The
equation
between
carbonate
acid
state
the
3
reaction
Using
for
2O
and
shows
all
calcium
hydrochloric
the
state
symbols
symbols:
State
symbols
show
us
the
state
of
a
CaCO
substance:
(s)
+
2HCl(aq)
3
→
CaCl
(aq)
+
2
(s)
=
solid,
(l)
=
liquid,
(g)
=
gas,
(aq)
=
aqueous
solution
CO
(g)
+
H
2
State
symbols
product,
e.g.
are
Cl
written
(g)
is
after
chlorine
the
formula
gas,
H
2
NaCl(aq)
is
O(l)
for
is
each
water,
reactant
H
2
aqueous
sodium
O(g)
is
EXAM
steam,
TIP
2
chloride.
writi
ng
equa
tions
,
identif
y
ionic
equation
part
in
a
compounds
is
a
symbol
reaction.
dissolve
equation
The
ions
in
water,
that
that
do
the
shows
not
ions
only
take
separate.
those
part
are
ions
called
An
that
ionic
take
that
will
To
write
an
ionic
are
Write
down
the
balanced
2NaBr(aq)
equation
with
state
symbols.
+
Cl
(aq)
→
2NaCl(aq)
+
Br
2
Identify
the
no t
to
ions.
be
T
hese
so lid
s
have
precipi
tated
,
equation:
For
example:
simple
or
gases,
e.g.
mole
cules
chlor
ine
2
need
produ
cts
gene
rally
liqui
ds
1
the
spectator
that
ions.
ionic
you
equations
When
2
and
When
Ionic
O(l)
or
such
carbon
(aq)
as
dioxi
de.
2
substances
that
are
ionic
and
write
down
the
ions
separately.
+
2Na
+
(aq)
+
2Br
(aq)
+
Cl
(aq)
→
2Na
(aq)
+
2Cl
(aq)
+
Br
2
3
Rewrite
the
equation,
(aq)
2
deleting
the
ions
that
are
the
same
KEY
1
+
each
side
of
the
equation:
in
this
case
the
Na
POINTS
on
The
of
2Br
(aq)
+
Cl
(aq)
→
2Cl
(aq)
+
Br
2
(aq)
two
solutions
are
mixed
and
a
precipitate
(solid)
is
mass
formed,
you
the
write
an
ionic
equation
in
the
following
Write
the
formula
of
the
precipitate
as
the
Write
down,
as
reactants,
the
ions
that
go
reaction,
products
mass
is
in
a
the
mass
equal
of
the
to
reactants.
There
is
the
same
number
of
product.
each
2
that
way:
2
1
conservation
can
the
generally
of
states
chemical
2
of
If
law
ions.
to
make
up
type
of
atom
on
each
the
side
of
a
chemical
equation.
precipitate.
3
3
Make
sure
that
the
equation
is
Equations
writing
of
For
example,
in
the
are
balanced
by
balanced.
a
number
particular
in
front
reactants
or
reaction:
products.
FeCl
(aq)
+
3NaOH(aq)
→
Fe(OH)
3
(s)
+
3NaCl(aq)
3
4

The
precipitate
is
Fe(OH)
Ionic
equations
show
only
(s).
the
3
species
that
react
to
3+

The
ions
that
go
to
make
up
the
precipitate
are
Fe
(aq)
and
OH
(aq).
form
the
product(s).
3+

The
ionic
equation
is:
Fe
(aq)
+
3OH
(aq)
→
Fe(OH)
(s)
3
51
6.3
Mole
LEARNING
At
the
end
should
be
OUTCOMES
of
this
able
topic
Simple
you
calculations
mole
Example
1:
(1)
calculations
mass
to
moles
to:
How
many
moles
of
magnesium
chloride,
MgCl
,
are
present
in
2

apply
the
mole
concept
to
38.2 g
of
magnesium
chloride?
(A
values:
Mg
=
24.3,
Cl
=
35.5)
r
molecular
and
ionic
equations
1
Calculate
the
molar
mass
of
MgCl
=
24.3
=
95.3 g mol
+
(2
×
35.5)
2

calculate
formed
the
mass
from
a
of
−1
product
given
reactant
2
or
vice
Use
the
relationship:
versa.
mass
number
of
moles
(g)
38.2
=
=
=
0.401 mol
–1
molar
Example
What
2:
mass
nitrate,
moles
of
calcium
Ca(NO
)
3
EXAM
to
?
(A
2
mass
(g mol
mass
nitrate
values:
is
N
present
=
it
is
in
14.0,
O
0.030 mol
=
16.0,
of
Ca
calcium
=
40.0)
r
Calculate
the
molar
mass
of
Ca(NO
)
3
chem
ical
the
95.3
TIP
1
In
)
impo
rtant
answ
er
num
ber
figu
res
to
to
the
give
2
40.0
+
2
Rearrange
×
the
[14.0
+
(3
equation
×
in
16.0)]
terms
=
of
164 g mol
mass:
co rrec
t
−1
mass
of
2
−1
=
calcu
latio
ns,
(g)
=
number
of
moles
(mol)
×
molar
mass
(g mol
)
sign
ifica
nt
that
fits
the
data
3
Substitute
the
values:
0.030
×
164
=
4.92 g
given.
355.
6
How
roun
ded
sign
ifica
nt
to
much
product
or
reactant?
3
figu
res
To
find
the
mass
of
products
formed
in
a
reaction
we
use:
is
356.
355.
6
roun
ded
sign
ifica
nt
to
2
figu
res
is

the
mass
of
a

the
molar

the
balanced
particular
mass
of
this
reactant
reactant
equation.
360.
Example
T
he
be
answ
er
the
given
same
num
ber
figu
res
of
in
as
the
(method
1)
Calculate
the
maximum
mass
of
iron
formed
when
798 g
of
oxide,
Fe
O
100%
conversion
2
,
is
reduced
by
excess
carbon
monoxide,
CO.
Assume
3
of
iron
oxide
to
iron.
(A
values:
O
=
16.0,
r
data.
C
1
=
12.0,
Fe
Write
the
given
this.
=
55.8)
balanced
Fe
O
2
2
Calculate
the
(s)
equation
+
for
3CO(g)
the
reaction.
→
2Fe(s)
+
You
will
3CO
3
usually
Fe
=
55.8
relevant
Fe
O
2
3
Multiply
each
balanced
(g)
formula
masses.
In
this
case,
for
Fe
O
=
(2
×
55.8)
+
formula
mass
e.g.
in
1 mol
grams
of
Fe
Fe
O
2
produces
3
2
×
by
O
2
of
(3
×
16.0)
=
and
Fe
3
159.6
3
equation,
159.6 g
be
2
2
52
iron( III)
least
sign
ifica
nt
the
1
shou
ld
the
number
produces
of
2 mol
moles
of
3
55.8 g
=
111.6 g
Fe
Fe,
in
so:
the
4
Use
simple
proportion
to
calculate
the
mass
of
iron
produced:
DID
YOU
KNOW?
111.6
×
798
=
558 g
Fe
The
German
scientist
Wilhelm
159.6
Ostwald
Example
1
(method
2)
‘mole’
first
in
relation
calculations
1
Write
the
balanced
equation
as
in
798
Calculate
the
number
of
moles
the
to
term
chemical
1893
by
before.
abbreviating
2
used
of
Fe
O
2
Molekül
=
=
the
German
word
(molecule).
5.0 mol
3
159.6
3
From
the
equation,
1 mol
Fe
O
2
So
5.0 mol
Fe
O
2
4
Calculate
mass
of
Example
Calculate
oxide,
iron
the
Pb
2 mol
Fe.
10.0 mol
Fe.
3
mass
=
of
10.0
iron
×
from
55.8
=
mass
=
558 g
mol
[Fe]
×
M
[Fe]
Fe
2
O
3
lead
the
produces
produces
3
minimum
,
to
form
mass
62.1 g
of
of
carbon
lead,
that
Pb.
reacts
Assume
with
100%
red
lead
conversion
of
4
oxide
to
lead.
(A
values:
C
=
12.0,
Pb
=
207)
r
1
The
balanced
equation
is:
Pb
O
3
+
4C
→
3Pb
+
4CO
4
62.1
2
Calculate
the
number
of
moles
of
Pb
=
=
EXAM
0.300 mol
TIP
207
3
From
the
equation,
3 mol
Pb
is
produced
from
4 mol
When
C.
doin
g
mo le
calcu
latio
ns,
So
0.300 mol
lead
is
produced
from
0.400 mol
C.
to
4
So
mass
mass
of
of
C
C
=
=
mol
0.400
[C]
×
×
M
12.0
[C]
=
take
the
4.80 g
into
num
ber
relev
ant
C
We
can
4.60 g
of
sulfide,
a
mole
sodium
Na
mo les
in
the
of
and
balanc
ed
equa
tion.
3
use
of
react
ants
produc
ts
Example
remem
ber
accoun
t
S.
calculation
is
reacted
Which
to
with
reactant
is
deduce
3.52 g
in
which
of
excess
reagent
sulfur
and
to
how
form
many
is
in
excess:
sodium
grams
of
the
2
excess
reagent
remain?
(A
values:
Na
=
23.0,
S
=
32.0)
r
1
Determine
the
number
of
moles
of
each
reactant:
4.60
mol
Na
3.52
=
=
0.200 mol
mol
S
=
=
23.0
2
Write
2Na
the
+
equation
S
→
0.110 mol
32.0
Na
and
S
determine
so
2 mol
the
Na
ratio
react
of
with
reacting
1 mol
of
moles.
S
KEY
POINTS
2
3
To
react
completely
with
0.200 mol
of
Na,
it
needs
1
½
×
0.200 mol
S
=
The
chemical
relative
4
So
S
is
5
Mass
in
excess
by
0.110
–
0.100
=
be
0.010 mol
S
in
excess
=
mol
[S]
×
M
The
reactant
reactant.
which
is
and
0.010
not
in
×
32.0
excess
in
of
to
masses
calculate
product
can
the
formed
[S]
from
=
formula
used
mass
of
equation
0.100 mol.
a
=
vice
0.320 g.
reaction
is
called
the
limiting
2
A
a
particular
or
versa.
limiting
one
reactant
reactant
which
is
not
in
is
the
excess.
53
6.4
Mole
calculations
Percentage
LEARNING
the
end
of
this
topic
be
percentage
composition
able
determine
%
percentage
of
by
mass
mass
is
given
by:
the
atomic
masses
of
a
by
element
compound
a
mass
of
element
in
a
compound)
=
×
molar
composition
in
by
to:
particular

mass
you
(sum
should
by
OUTCOMES
The
At
composition
(2)
mass
of
the
100
compound
an
Example

carry
out
calculations
involving
gas
volumes
at
Calculate
the
(NH
.
)
4
and
calculate
moles
gas
SO
2
(A
4
values:
by
H
=
mass
1.0,
)
SO
N
of
=
nitrogen
14,
O
=
in
ammonium
16,
S
=
sulfate,
32)
r
s.t.p.
1

percentage
r.t.p.
in
and
the
a
number
given
vice
Molar
mass
of
(NH
of
4
volume
2
=
2
×
[14
+
=
132 g mol
(4
×
1)]
+
32
+
(4
×
16)
4
of
−1
versa.
2
In
1 mol
of
(NH
)
4
So
the
sum
of
SO
2
there
are
2 mol
of
N
atoms.
4
these
atomic
masses
is
=
14
+
14
=
28
28
3
%
by
mass
of
N
=
×
100
=
21.2%
132
(21%
Using
In
6.1
Avogadro’s
we
learnt
temperature
At
room
that
and
2
significant
figures)
law
equal
pressure
temperature
to
volumes
have
and
the
of
all
same
pressure
gases
at
number
(r.t.p.)
the
of
one mole
same
molecules.
of
any
gas
3
occupies
24.0 dm
.
This
is
called
the
molar
gas
volume
(V
)
at
r.t.p.
m
Room
temperature
mercury)
At
and
pressure
is
20 ºC
and
1 atmosphere
(760 mm
pressure.
standard
temperature
and
pressure
(s.t.p.)
one
mole
of
gas
3
occupies
22.4 dm
Standard
.
This
temperature
(760 mm
mercury)
Applying
Avogadro’s
form
called
and
the
molar
pressure
is
gas
0 ºC
volume
and
at
s.t.p.
1 atmosphere
pressure.
law
to
the
reaction
of
hydrogen
with
oxygen
steam:
2H
(g)
+
O
2
2 mol
2
(g)
→
2H
2
1 mol
volumes
1
O(g)
2
2 mol
volume
3
2
volumes
3
48 dm
3
24 dm
48 dm
3
From
Figure
6.4.1
The
anaesthetist
know
about
gas
needs
to
this
we
using
with
25 cm
administer
we
react,
for
example,
50 cm
of
hydrogen
3
of
oxygen,
law
in
we
mole
get
50 cm
calculations
of
steam.
because,
anaesthetics.
of
molecules
in
the
same
volume
of
gaseous
s.t.p.,
54
if
if
We
can
there
use
are
equal
equipment
numbers
to
that
volumes
Avogadro’s
when
see
3
there
are
also
equal
numbers
of
moles.
gas
at
either
r.t.p.
or
to
Example
1
EXAM
−1
Calculate
the
methane
gas
mass
at
of
methane
(M
=
16 g mol
1
Change
in
480 cm
of
Mak
e
r.t.p.
3
volume
in
cm
volume
in
dm
sure
know
3
to
TIP
3
)
how
that
to
:
dm
3
and
dm
480
3
3
=
=
3
cm
3
into
480 cm
you
conv
ert
into
3
cm
0.480 dm
.
1000
3
cm
2
Calculate
the
number
of
moles
volume
(dm
)
cm
by
0.480
=
=
dm
:
3
divide
3
3
→
using:
1000
0.020 mol
3
24
3
Calculate
mass
Example
Calculate
mass
(g)
=
using:
moles
×
M
=
0.020
×
16
=
0.32 g
3
→
multip
ly
cm
:
3
dm
by
1000
methane
2
the
values:
(A
dm
24
C
volume
=
of
12.0,
O
3.08 g
=
of
carbon
dioxide
at
s.t.p.
EXAM
TIP
16.0)
r
Mak
e
1
Calculate
moles
of
CO
carry
ing
mass
moles
2
=
Calculate
the
when
out
3.08
=
molar
sure,
using:
2
mass
volume
=
12.0
+
(2
×
calcu
latio
ns
0.070 mol
16.0)
gas
using:
invo
lving
vo lum
es,
you
check
that
whe th
er
the
3
volume
=
moles
×
molar
volume
in
dm
at
s.t.p.
cond
ition
s
s.t.p.
3
=
0.070
×
22.4
=
1.57 dm
(to
3
significant
figures)
of
Example
becaus
e
1 mo
l
with
3
of
the
propane,
volume
C
H
3
(A
values:
H
,
is
of
carbon
completely
dioxide
burnt
formed
in
excess
at
r.t.p.
when
of
a
r
.t.p.
the
with
0.88 g
or
vo lum
e
gas
varie
s
tempe
rature.
varie
s
Calculate
are
It
also
pressu
re.
oxygen.
8
=
1.0,
C
=
12,
O
=
16)
r
1
Calculate
the
number
of
moles
of
propane:
KEY
POINTS
0.88
=
0.020 mol
1
(3
×
12)
+
(8
×
The
percentage
element
2
Write
the
balanced
equation
for
the
reaction
and
identify
mole
H
3
+
5O
8
→
Calculate
the
3CO
2
+
4H
2
1 mol
3
a
mass
compound
of
an
can
calculated
using
the
relative
ratios:
atomic
C
in
the
be
relevant
by
1.0)
and
O
of
moles
of
the
of
relative
the
element
formula
mass
2
of
3 mol
number
mass
CO
2
:
the
One
compound.
mole
of
any
gas
occupies
2
3
24 dm
0.020 mol
C
H
3
4
Calculate
the
volume
→
0.020
×
3
=
0.060 mol
2
CO
at
2
(dm
)
and
3
moles
×
V
=
pressure
(r
.t.p.).
0.060
×
24
=
One
mole
of
any
gas
3
3
=
temperature
r.t.p.:
3
volume
room
CO
8
of
at
occupies
1.4 dm
22.4 dm
at
m
standard
(to
2
significant
temperature
and
figures)
pressure
4
(s.t.p.).
Avogadro’s
to
a
calculate
given
given
the
mass
calculate
a
law
the
of
can
be
used
volume
gas
mass
or
of
of
to
gas
in
volume.
55
Section
Objectives
1
The
one
Summary
states
of
matter
can
State
b
converted
8
the
9
D
name
of
the
changes
A,
B,
Which
using
two
of
of
ideas
these
changes
energy?
about
occur
Explain
forces
with
your
between
the
answer
of
the
the
arrangement,
particles
Define
arrangement
a
an
atom
of
carbon
b
an
atom
of
sodium.
in
a
solid,
closeness
a
liquid
and
and
Define
the
the
of:
terms:
a
isotopes
b
mass
c
relative
d
allotropes.
a
motion
number
Potassium
atomic
mass
but
water
chloride
is
a
has
simple
a
giant
ionic
structure
molecule.
gas.
a
3
electron
particles.
10
Describe
the
C
D.
absorption
2
Write
C
B
and
be
another.
A
a
questions
A1–6
three
into
A
State
three
properties
terms:
differences
of
potassium
in
the
physical
chloride
and
water.
a
element
b
compound
b
Draw
dot-and-cross
potassium
c
diagrams
Show
for
the
electrons
in
solvent.
each
4
chloride.
Three
different
mixtures
of
dyes,
A,
B
and
c
were
spotted
onto
a
piece
of
electron
Draw
a
T
wo
pure
dyes,
D
and
E,
were
on
the
same
piece
of
only
the
outer
diagram
electron
for
water.
shells.
also
11
spotted
dot-and-cross
chromatography
Show
paper.
shell.
C,
The
diagram
shows
the
structure
of
diamond
paper.
and
graphite.
Both
contain
carbon
atoms.
Graphite
A
B
C
D
E
Diamond
a
Which
mixture
number
of
contained
different
the
greatest
dyes?
a
b
Which
dye
mixture
contained
both
D
and
E?
Describe
structures
which
5
Explain
the
colloids,
particle
differences
suspensions
size
and
light
in
properties
and
solutions
A
crystal
of
a
terms
b
of
red
Explain
have
scattering.
water-soluble
dye
was
a
had
beaker
of
water
.
disappeared
spread
After
and
throughout
the
the
24
red
hours,
colour
water
.
the
using
the
Explain
moving
Describe
the
type,
number
and
Explain
both
why
why
present
in
particle
charge
an
12
ways
in
and
graphite
points.
diamond
graphite
is
is
used
used
as
for
a
drill
atom
tips
lubricant.
Zinc
is
a
metal
but
sulfur
is
a
non-metal.
State
four
differences
in
the
physical
theory.
of
the
of
Cl.
17
56
these
these
b
Draw
a
of
zinc
diagram
bonding
particles
two
diamond
melting
35
subatomic
and
which
differ.
why
high
properties
7
similar
in
crystal
had
a
observations
ways
placed
and
in
are
they
other
between
in
c
6
two
in
zinc.
and
to
sulfur.
show
the
metallic
13
Write
balanced
equations
including
following
reactions:
state
(A :
H
=
1,
Cl
=
35.5,
Fe
=
56)
Fe
needed
r
symbols
for
the
b
a
solid
aluminium
chloride
+
water
forming
the
minimum
produce
10 g
mass
of
hydrogen,
to
H
2
aluminium
hydroxide
and
hydrogen
20
chloride
Describe
of
b
calcium
and
carbonate
+
hydrochloric
the
Group
calcium
chloride,
carbon
the
trend
elements
in
with
reactivity
aqueous
of
their
sodium
halides.
dioxide
21
When
calcium
reacts
with
water,
an
alkaline
water.
solution
c
VII
acid
solutions
forming
and
explain
gas
aqueous
lead(II)
aqueous
potassium
nitrate,
Pb(NO
)
3
,
formed.
+
2
a
iodide
is
forming
Write
a
balanced
symbols,
iodide,
PbI
,
+
potassium
equation,
including
state
lead( II)
for
the
reaction
of
calcium
with
nitrate.
2
water.
14
Write
ionic
equations
for
these
reactions:
b
a
Cl
(aq)
+
2NaBr(aq)
→
Br
2
water
+
CuCl
(aq)
+
2NaOH(aq)
→
Cu(OH)
2
+
(aq)
+
Na
2
SO
2
(aq)
→
BaSO
Describe
and
of
chemical
the
maximum
produced
(A :
C
butane
=
the
volume
(measured
12,
O
burns
=
3
in
trends
terms
in
of
the
their
physical
properties.
(s)
Describe
how
of
in
at
r.t.p.)
excess
you
of
could
the
separate
following
the
mixtures.
In
carbon
case
explain
the
theory
behind
the
when
separation
of
with
slowly.
2NaCl(aq)
each
5.6 g
explain
Period
components
dioxide
very
4
23
Calculate
rapidly
reacts
2NaCl(aq)
4
+
15
reacts
(s)
and
BaCl
calcium
magnesium
2
elements
c
why
but
2NaCl(aq)
22
b
Explain
(aq)
2
method.
air.
a
a
mixture
of
b
a
mixture
salt
(sodium
chloride)
and
sand
16)
r
C
H
4
+
6O
8
→
4CO
2
+
4H
2
where
16
Calculate
the
mass
of:
a
0.50 mol
HCl
b
0.20 mol
Ca(NO
c
0.015 mol
B
24
)
3
of
two
miscible
liquids
A
and
B,
O
2
State
iron
has
A
a
a
boiling
boiling
three
and
has
point
differences
sulfur
and
a
point
of
of
140 °C
and
165 °C.
between
compound
a
mixture
of
iron
of
and
2
sulfur
.
Na
SO
2
(A :
H
=
1,
C
=
4
12,
N
=
14,
O
=
16,
25
Draw
dot-and-cross
diagrams
for:
r
Na
17
=
23,
Calculate
S
=
the
32,
Cl
=
number
35.5,
of
Ca
moles
=
40)
of:
a
an
oxygen
b
the
ionic
molecule
compound
calcium
fluoride,
CaF
2
a
bromine
molecules,
Br
,
in
1.2 g
2
(A :
Br
=
Br
In
each
case,
show
only
the
outer
shell
2
80)
electrons.
r
b
iron
atoms
in
19.2 g
of
Fe
O
2
(A :
O
=16,
Fe
=
26
3
chloride
ions
in
79.17 g
for
the
following
ionic
MgCl
2
(A :
formulae
compounds:
r
c
Write
56)
Mg
=
24.3,
Cl
=
a
aluminium
sulfate
b
magnesium
35.5)
r
nitride
(the
symbol
for
the
3–
18
Define
19
Iron
the
term
mole
nitride
c
reacts
with
excess
hydrochloric
acid
iron(III)
ion
is
oxide
N
)
(the
symbol
for
an
iron( III)
ion
to
3+
is
form
iron(II)
Fe
2HCl
chloride
and
d
+
→
FeCl
+
Fe
)
hydrogen.
magnesium
nitrate.
H
2
2
27
Is
carbon
disulfide,
Calculate:
the
,
an
ionic
or
covalent
2
compound?
a
CS
maximum
mass
of
FeCl
formed
Give
a
reason
for
your
answer.
when
2
28 g
Fe
reacts
with
excess
HCl
57
7
Acid,
bases
7.1
and
Acids
What
LEARNING
the
end
of
this
topic
be
acids
and
usually
able
bases?
have
The
a
sour
taste,
commonest
sulfuric
acid,
H
SO
2
define
alkali,

acid,
base
explain
change
inorganic
blue
litmus
acids
are
acid
and
acids
anhydride,
form
salt
and
definition
a
of
salt
an
acid
and
is
water.
(aq)
and
nitric
acid,
HNO
4
that
of
For
are
is
a
substance
that
(aq).
A
neutralises
simple
a
base
to
example:
+
CaO(s)
→
CaCl
(aq)
+
H
O(l)
2
replaceable
acid
hydrogen
and
acid,
3
it
2
terms
red,
bases
2HCl(aq)
in
to
hydrochloric
to:
HCl(aq),

bases
you
corrosive.
should
and
OUTCOMES
Acids
At
are
salts
and
proton
base
salt
water
transfer.
Acids
have
one
or
more
replaceable
hydrogen
atoms.
The
+
hydrogen
is
replaced
by
a
metal
or
ammonium
ion,
NH
.
In
the
4
reaction
above,
the
hydrogen
in
the
acid
is
replaced
by
the
calcium
ion.

Monobasic

Dibasic
acids
acids
have
have
one
two
replaceable
replaceable
hydrogen
hydrogen
atom,
atoms,
e.g.
e.g.
HCl.
sulfuric
acid:
H
SO
2

Tribasic
(aq)
+
CaO(s)
base
water.
A
acids,
7.1.1
All
these
a
e.g.
H
substance
Bases
base
the
Figure
is
that
Group
I
CaSO
are
is
(aq)
+
H
4
PO
3
A
→
4
soluble
have
three
replaceable
hydrogen
atoms.
4
that
often
metals,
,
O(l)
2
neutralises
oxides
in
e.g.
and
water
is
NaOH,
an
acid
hydroxides
called
and
an
to
of
form
salt
and
metals.
alkali.
aqueous
a
The
hydroxides
ammonia,
NH
(aq),
of
are
3
household
alkalis.
products
contain
acids.
Salts
A
EXAM
T
he

sign
salt
is
a
replaced
TIP
→
is
Chloride
the
react
compl
e tion.
acids
and
react
ion
ion
salts
goes
alwa
ys
T
he
does
and
when
no t
bo th
produc
ts
7
.2).
acids
T
his
and
goes
Sulfates
H
to
are
+
Ca(OH)
SO
formed
(aq)
→
CaCl
in
an
acid.
is
example,
(aq)
+
from
(aq)
+
2H
O(l)
sulfuric
2NaOH(aq)
acid.
→
2
For
Na
example,
SO
2
(aq)
+
sodium
2H
4
sulfate:
O(l)
2
Nitrates
are
formed
nitric
acid.
For
example,
potassium
nitrate:
to
(aq)
+
KOH(aq)
→
KNO
3
(aq)
+
3
H
O(l)
2
and
presen
t
applies
from
react
ion
Proton
transfer
in
acids
and
bases
(see
weak
When
an
acid
Hydrogen
chloride
dissolves
ions
gas
are
in
water,
formed.
ionising
in
The
water
it
ionises
equation
(splits
below
up
into
shows
+
(aq).
(aq)
→
H
(aq)
+
Cl
ions).
hydrogen
+
HCl(g)
58
acid
For
2
4
compl
e tion
bases.
hydrochloric
2

the
react
ants
are
from
hydrogen
sign
the
to
formed
the
ion.
chloride:
HNO
go
when
ammonium
strong

used
are
formed
or
to
2
is
metal
2HCl(aq)
For
bases,
compl
e tion.
a
used
calcium
when
compound
by
(aq)
When
an
alkali
dissolves
in
water,
it
ionises
and
forms
hydroxide
ions:
+
NaOH(s)

We
can
+
define
(aq)
acids
→
and
Na
(aq)
bases
in
+
OH
terms
(aq)
of
the
transfer
of
hydrogen
DID
YOU
KNOW?
ions.
+
The
H
O
ion
which
is
formed
3

In
talking
about
acids
and
bases,
a
hydrogen
ion
is
called
a
proton.
when


An
A
acid
base
is
is
a
a
proton
proton
donor
–
it
acceptor
gives
–
it
one
takes
or
one
more
or
protons
more
to
protons
a
base.
from
an
is
called
(or
in
ions.

Hydrochloric
acid
is
an
acid
because
when
it
dissolves
in
water,
acid
the
a
proton
to
ion).
solution
Unless
in
water
So
are
we
really
are
ion
hydrogen
these
being
very
it
accurate,
donates
dissolves
hydroxonium
oxonium
ions
acid.
an
we
usually
just
write
water:
+
H
(aq)
for
a
hydrogen
ion
in
+
donated
H
solution.
+
HCl(g) + H
→
O(l)
H
2
O
(aq) + Cl
be
Ammonia
is
a
most
an
applied
modern
acid
to
is
wider
solutions
and
in
base
solvents

of
3
can
acid
The
definition
(aq)
base
because
it
accepts
a
proton
from
other
than
water
.
water:
+
donated
H
+
NH
(g) + H
3
O(l)
NH
2
base
(aq) + OH
(aq)
EXAM
4
In
You
can
see
that
water
can
act
as
either
an
acid
or
a
base
organi
c
H
2
what
is
dissolved
in
it.
A
substance
that
can
act
as
an
acid
or
is
described
as
5
for
can
the
simplify
ionisation
of
some
the
equations
for
the
acids
ionisation
of
acids
by
water.
For
in
+
SO
2
(l)
→
2H
the
+
SO
ionis
es.
is
COOH
only
the
ionis
es.
grou
p
It
is
is
this
H
repla
ceable.
(aq)
4
For
is
a
compound
example,
carbon
that
dioxide
forms
forms
an
acid
when
carbonic
acid
it
reacts
and
DID
dioxide
forms
sulfurous
YOU
(g)
+
H
2
SO
O(l)
H
2
(g)
+
H
2
CO
2
O(l)
H
2
SO
2
talk
about
cannot
(aq)
2
A
because
3
The
neutralises
a
base
to
form
a
salt
and
water.
neutralises
hydrogen
ammonium
4
An
alkali
5
Acids
6
An
are
acid
reacts
is
in
an
acid
to
form
a
salt
and
water.
acid
can
acid,
of
it.
you
This
be
replaced
by
a
metal
of
the
acid
in
is
really
a
hydrogencarbonate
dioxide
ions,
and
dissolved
hydrogen
water.
or
ion.
a
base
proton
that
is
donors
anhydride
with
an
bottles
carbonate
carbon
ions
base
get
mixture
ions,
acid
chemists
carbonic
3
is
An
many
(aq)
3
POINTS
1
KNOW?
acid:
Although
CO
KEY
it
),
in
2−
(aq)
4
anhydride
water.
sulfur
as
anhydrides
acid
with
13.5
hydr
ogen
example:
H
An
such
ignoring
that
Acid
(see
mo lec
ule
which
the
the
Rem
embe
r
H
We
all
amphoteric
the
Equations
COOH
a
no t
base
acids
according
C
to
TIP
acid
is
a
soluble
and
in
bases
compound
water.
are
that
proton
forms
acceptors.
an
acid
when
it
water.
59
7.2
Acidity
The
LEARNING
the
end
of
this
topic

relate
the

be
able
acidity
pH
pH
to
scale
is
show
how
a
scale
of
acidic
numbers
or
from
alkaline
a
0
to
14
solution
(Figure
7.2.1).
It
is
is.
to:
and
alkalinity

A
pH
below

A
pH
above

A
pH
of
7
is
acidic.
to
7
is
alkaline.
scale
describe
the
universal

scale
you
used
should
alkalinity
OUTCOMES
The
At
pH
and
describe
use
of
litmus
exactly
7
is
neutral.
and
indicator
the
strength
of
acids
Neutral
and
alkalis
related
to
degree
pH
of

0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
ionisation
describe
the
between
difference
strength
concentration
of
of
Strongly
acid
7.2.1
Finding
Using
that
the
acidity
lower
the
pH
lower
the
acidity
high
er
Strongly
alkaline
alkaline
The
the
pH
scale
pH
universal
the
indicator
the
Universal
er
Weakly
TIP
Rem
embe
r
high
acidic
acid.
Figure
EXAM
Weakly
acidic
and
and
the
a
the
the
pH.
range
indicator
of
colours
indicator
is
matched
against
different
colours.
0
pH
dipped
1
Figure
a
2
7.2.2
a
We
can
the
pH
pH
use
of
accurate
pH
pH
a
a
mixture
in
the
chart
4
Universal
of
on
coloured
the
solution
colour
3
the
Using
is
depending
5
indicator
pH
under
test
showing
6
7
changes
compounds
(Figure
the
and
pH
8
colour
7.2.2).
the
that
The
shows
universal
colour
is
corresponding
9
10
according
to
11
12
the
pH
to
13
14
of
solution.
meter
a
pH
electrode
solution
value
of
connected
directly
pH
than
(Figure
universal
to
a
7.2.3).
pH
A
meter
pH
to
meter
measure
gives
a
more
indicator.
meter
electrode
The
litmus
test
Solution
under
test
A
meter
Litmus
is
coloured
Figure
7.2.3
pH
can
be
find
the
exact
pH
of
60
compound
or
indicator.
mixture
of
An
acid–base
coloured
indicator
over
a
specific
pH
range.
Litmus
is
compounds
blue
in
alkaline
is
that
a
changes
solutions
a
and
solution.
acid–base
used
colour
to
an
red
in
acidic
solutions.
It
changes
colour
around
pH
7.

Acids
turn

Alkalis
damp
turn
blue
damp
red
litmus
red.
litmus
blue.
EXAM
Concentrated
or
dilute?
It
A
concentrated
TIP
solution
of
an
acid
contains
more
particles
of
acid
is
the
inco rr
ect
wo rd
s
to
use
‘strong
’
or
3
per
dm
than
anything
a
dilute
about
how
solution
well
the
(see
acid
Figure
7.2.4).
It
does
not
tell
us
‘ weak
’
ionises.
to
the
conc
acids
a
when
in
referr
ing
entra
tion
mo l dm
of
−3
.
Y
ou
b
Water
molecules
+
H
ions
Cl
Concentrated
HCl (aq)
Dilute
shou
ld
7.2.4
a
A
concentrated
solution
of
acid,
b
a
dilute
solution
of
in
weak
acids
YOU
and
KNOW?
equations
weak
water
acids
Hydrochloric,
and
strong
sulfuric
and
bases
nitric
are
→
ionise
acids
H
completely
are
strong
in
acids,
solution.
reactions,
e.g.:
of
acid
I
hydroxides
are
strong
+
Cl
bases,
→
Na
e.g.:
more
the
(aq)
+
OH
acids
and
weak
bases
ionise
these
and
ions
constant
at
only
temperature.
hydrogen
position
of
ions
this
Adding
will
alter
equilibrium
(aq)
so
Weak
In
concentrations
(aq)
+
NaOH(aq)
acids
of
reactions.
the
remain
constant
Group
examples
molecules
formed
(aq)
weak
dissolving
bases
+
HCl(aq)
for
bases)
equilibrium
Strong
‘dilu
te’.
acid
(and
and
term
s
or
HCl (aq)
The
Strong
the
ions
DID
Figure
use
‘conc
entra
ted’
partially
in
solution.
that
more
un-ionised
acid
is
There
formed.
are
many
there
more
are
ions.
products
and
molecules
We
use
of
the
reactants
are
un-ionised
double
acid
arrow
present
in
or
(
)
what
we
base
to
present
show
call
an
than
that
both
equilibrium
KEY
POINTS
reaction.
Organic
acids
such
as
ethanoic
acid,
CH
OOH,
are
weak
1
acids.
The
pH
scale
is
used
to
show
3
the
degree
of
acidity
or
+
CH
COOH(aq)
H
(aq)
+
CH
3
Ammonia
COO
(aq)
3
is
an
example
of
a
weak
alkalinity
of
a
solution.
base.
2
Solutions
with
pH
below
+
NH
(g)
+
3
H
O(l)
NH
2
(aq)
+
OH
7
(aq)
are
acidic,
above
T
able
at
7.2.1
two
compares
different
and
solutions
4
the
pH
values
concentrations.
At
of
the
typical
same
weak
acids
and
concentration,
pH
7
are
alkaline.
bases
strong
3
Universal
indicator
can
be
+
acids
weak
have
a
acids.
lower
the
greater
For
a
concentration
given
of
H
concentration,
ions
the
and
a
stronger
lower
the
pH
acid
used
than
is,
find
the
pH
of
a
solution.
the
pH.
4
Blue
Red
T
able
to
7.2.1
pH
values
of
strong
and
weak
acids
and
litmus
litmus
turns
turns
red
blue
in
acid.
in
bases
alkali.
Concentration
pH
of
pH
of
pH
of
pH
of
5
Strong
acids
are
completely
−3
(mol dm
1.0
)
strong
0
acid
weak
acid
2.4
strong
base
14
weak
base
11.6
ionised
acids
in
are
solution.
partially
Weak
ionised
in
solution.
0.1
2
3.4
12
10.6
61
7.3
The
reaction
acids
Four
LEARNING
the
end
of
this
topic
be
types
bases
of
oxide
Acidic
able
oxides
react
with
alkalis
to
form
a
salt
and
water.
Many
you
of
should
different
some
OUTCOMES

At
and
of
them
also
react
with
water
to
form
acids.
They
are
all
oxides
of
to:
non-metals.

describe
oxides
as
acidic,
CO
(g)
+
2NaOH(aq)
→
Na
2
basic,
amphoteric
or


describe
some
reactions
Basic
oxides
react
with
Group
II
oxides
salts
and
between
describe
with
acid

the
Li
salts
reaction
ammonium
explain
how
removed
nitrogen
from
of
bases

salts
+
H
O(s)
the
Amphoteric
oxide
alkalis
is
soil
reacts
to
when
is
added
with
the
to
form
a
salt
and
with
water
to
SO
(aq)
→
CuSO
4
form
Al
O
2
soil.
(aq)
and
+
+
H
oxides
with
O
O(l)
→
and
H
O(l)
2LiOH(aq)
react
acids
to
with
form
both
acids
aluminium
and
salts
alkalis.
and
Aluminium
water,
and
with
aluminates.
(s)
+
6HCl(aq)
→
2AlCl
3
(aq)
+
3H
3
O(l)
2
(s)
+
2NaOH(aq)
→
2NaAlO
zinc
with
(aq)
+
H
2
oxide
alkalis
to
reacts
form
with
acids
zincates,
to
e.g.
O(l)
2
aluminate
form
Na
zinc
salts
and
water,
ZnO
2
2
KNOW?

Although
I
2
3
Similarly
YOU
Group
hydroxides.
4
sodium
DID
water.
fertilisers
Al
to
O(l)
2
2
form
2
lime
H
normal
2

acids
react
2
distinguish
+
acids
CuO(s)

(aq)
3
of
some
non-oxidising
CO
2
neutral
carbon
monoxide,
Neutral
N
O,
oxides
and
do
not
nitrogen( II)
react
oxide,
with
NO,
acids
are
or
neutral
alkalis.
Nitrogen( )
oxide,
oxides.
2
CO,
a
is
sometimes
neutral
oxide,
classified
it
can
also
as
be
Reactions
classified
oxide
as
a
very
because
water
under
it
weak
does
high
react
pressure
methanoic
acids
with
Reaction
with
metals
to
Most
give
of
acidic
acids
react
with
reactive
metals
to
form
a
salt
and
hydrogen.
acid.
Full
equation:
Mg(s)
+
2HCl(aq)
→
MgCl
(aq)
+
H
2
+
Ionic
equation:
Mg(s)
+
2H
(g)
2
2+
(aq)
→
Mg
(aq)
+
H
(g)
2
DID
YOU
Nitric
with
acid
Reaction
KNOW?
does
metals
to
not
always
form
a
salt
react
Acids
This
is
because
it
is
react
It
oxidises
agent
metals
to
(see
metal
carbonates
releases
oxides
of
form
a
salt,
carbon
dioxide
and
water.
CO
(s)
+
H
3
SO
2
(aq)
→
Na
4
SO
2
(aq)
+
CO
4
(g)
+
H
2
O(l)
2
8.2).
salts
Ionic
equation:
2−
and
to
hydrogencarbonates
equation:
2
oxidising
with
and
a
Na
good
carbonates
and
Full
water
.
with
CO
nitrogen.
+
(s)
+
2H
(aq)
→
CO
3
Acids
Full
react
(g)
+
H
2
with
equation:
hydrogencarbonates
KHCO
(s)
+
HCl(aq)
in
a
→
3
similar
O(l)
2
way.
KCl(aq)
+
CO
(g)
+
2
H
O(l)
2
+
Ionic
equation:
HCO
(s)
3
62
+
H
(aq)
→
CO
(g)
2
+
H
O(l)
2
Reaction
Acids
with
react
bases
with
oxides
to
form
a
salt
and
water.
EXAM
Full
equation:
CuO(s)
+
2HCl(aq)
→
CuCl
(aq)
+
H
2
Y
ou
2−
Ionic
equation:
O
+
(s)
+
2H
(aq)
TIP
O(l)
2
→
H
mus
t
distin
guis
h
O(l)
2
caref
ully
Acids
react
with
hydroxides
to
form
a
salt
and
be tw
een
amm
onia,
water.
NH
,
and
the
3
amm
oniu
m
Full
equation:
NaOH(aq)
+
HNO
(aq)
→
NaNO
3
−
Ionic
equation:
OH
(aq)
+
H
3
acid
from
salts
the
a
mo lec
ule.
+
(aq)
+
H
salt
H
or
(aq)
→
H
Amm
oniu
m
O(l)
ionic
compo
unds
salts
.
salt
by
one
tribasic
or
hydrogen
more
in
metal
the
acid
atoms.
has
Acid
only
salts
been
are
formed
acids.
formation:
SO
2
(aq)
+
2NaOH(aq)
→
Na
4
SO
2
(aq)
+
2H
4
O(l)
2
formation:
H
SO
2
can
replaceable
replaced
dibasic
Normal
You
is
salts
partially
Acid
.
4
Amm
onia
are
In
+
NH
O(l)
2
2
Acid
ion,
(aq)
+
NaOH(aq)
→
NaHSO
4
see
(aq)
+
H
4
that
the
mole
ratio
of
alkali
to
acid
O(l)
2
is
lower
for
the
acid
salt.
KEY
The
reaction
of
bases
with
ammonium
1
Bases
react
gently
with
heated.
ammonium
For
salts
to
release
POINTS
salts
ammonia
especially
if
example:
Acidic
oxides
bases,
and
with
salt
NH
Cl(s)
+
NaOH(aq)
→
NH
4
(g)
+
NaCl(aq)
+
H
3
type
of
reaction
is
sometimes
a
Farmers
add
fertilisers
to
the
soil
problem
to
for
the
fertiliser
is
incorporated
into
help
crops
grow.
The
Fertilisers
such
as
ammonium
plant
sulfate
is
Many
acids
react
metals
with
to
form
acidic.
Crops
do
not
grow
if
ammonium
chloride
Carbonates
and
are
the
soil
is
too
So
farmers
add
lime
to
the
soil
to
neutralise
the
acids
Lime
reacts
with
water
in
the
soil
to
form
calcium
hydroxide.
hydroxide
is
called
slaked
and
+
H
O(l)
→
Ca(OH)
2
Basic
Lime
or
slaked
produce
lime
reacts
with
react
oxides
ammonium
salts
in
the
fertilisers
Cl(s)
+
Ca(OH)
(aq)
→
2NH
2
In
acid
(g)
+
CaCl
3
(aq)
+
2
2H
O(l)
been
NH
(s)
+
OH
(aq)
→
NH
(g)
+
3
H
a
water.
salts
only
in
the
replaceable
the
acid
partially
has
replaced
one
or
more
metal
atoms.
O(l)
6
Nitrogen
is
a
gas,
so
it
escapes
into
the
atmosphere.
This
results
of
nitrogen
from
the
ammonia
added
may
suffer
from
the
soil
gas
with
when
fertilisers
lime
to
soil.
the
growth
lost
in
is
loss
is
2
as
Ammonia
Plant
metals
form
−
4

to
2
by
a
and
acids
equation:
+

with
hydrogen
4
Ionic
the
reactive
to
equation:
2NH
and
of
ammonia.
5
Full
salt,
(aq)
2
salt

a
dioxide.
lime.
hydroxides
CaO(s)
form
carbon
Solid
4
calcium
to
acidity.
water

react
acidic.
with

salt
protein.
and
well
a
hydrogen.
hydrogencarbonates
slightly
a
formed.
nitrogen
3

water
react
cases
farmers:
and
in
oxides
both
O(l)
reactive

In
with
2
2
This
basic
acids.
and
react
because
of
the
lack
of
soil.
nitrogen.
63
7.4
Uses
of
acids
and
carbonates
Uses
LEARNING
of
carbonates
OUTCOMES
Antacids
At
the
should
end
be
of
this
able
topic
you
Indigestion
to:
(heartburn)
hydrochloric

describe
the
reaction
of
antacids
and
in
is
the
caused
by
stomach.
the
production
Many
antacids
of
excess
contain
magnesium
acids
carbonate,
with
acid
calcium
carbonate,
magnesium
hydroxide
or
sodium
baking
hydrogencarbonate
to
neutralise
the
excess
acid.
powder

describe
the
use
of
Baking
hydrogencarbonates
in
powder
fire
Baking
powder
is
used
to
make
cakes
rise.
It
contains
two
solids:
sodium
extinguishers
hydrogencarbonate

list
examples
of
acids
in
and
a
salt
of
a
weak
acid,
tartaric
acid.
When
added
living
to
the
liquid
in
the
cake
mix,
these
two
compounds
dissolve
and
react
to
systems
form

explain
how
content
of
the
fruit
determined
vitamin
juice
using
an
dioxide.
Fire
be
carbon
dioxide
makes
the
cake
rise.
extinguishers
indicator
foam
fire
extinguishers
contain
sodium
hydrogencarbonate
and
DCPIP
.
nitrogen
under
reduced
and
decomposes
carbon
from
These
products
well
sodium
the
heat
the
valve
is
opened,
hydrogencarbonate
to
form
extinguishes
the
carbon
fire
by
foam
dioxide.
the
is
formed.
The
preventing
pressure
foam
oxygen
is
This
containing
in
the
especially
fire
air
it.
acid
acid,
in
HCOOH,
stinging
is
found
nettles.
The
naturally
ants
bite
in
ants,
their
prey
to
ants,
immobilise
contain
them.
sodium
as
When
acids
Methanoic
7.4.1
in
reaching
Methanoic
as
pressure.
the
dioxide
Natural
Figure
The
C
can
Dry
called
carbon
But
we
can
also
get
bitten
by
ants.
Methanoic
acid
is
a
weak
hydrogencarbonate.
acid
but
is
dab
to
is
a
the
powerful
bite
skin
with
a
irritant.
dilute
A
household
solution
of
remedy
ammonia
(a
for
an
weak
ant
bite
base).
Vinegar
Vinegar
is
ethanoic
made
acid,
by
CH
fermenting
COOH,
a
plant
weak
material.
acid,
is
During
produced.
the
This
fermentation,
gives
vinegar
3
its
sharp
because
Lactic
Lactic
Figure
7.4.2
Pepper
sauce
condiment
people
is
a
with
favourite
many
throughout
Caribbean.
Vinegar
the
is
acid
enough.
low
pH
present
exercise.
In
very
used
prevents
the
milk.
to
preserve
bacterial
It
muscle
absence
for
Under
while.
in
Our
in
a
is
the
of
absence
these
also
cells
energetically,
(respiration
some
types
of
food
(pickling)
growth.
use
oxygen
oxygen,
of
builds
conditions
in
oxygen
cannot
the
oxygen)
up
for
get
muscle
so
lactic
our
our
muscles
respiration.
to
cells
the
is
When
muscles
respire
muscle
acid
under
cells
keep
produced
fast
anaerobically
in
working
the
an
T
oo
much
lactic
acid
in
the
lactic
acid
can
muscles
produces
cramps.
When
ingredient.
stop
64
is
exercise
muscles.
important
the
Vinegar
acid
extreme
we
taste.
exercising,
the
be
converted
to
glucose
in
the
liver
.
we
Lime
Lime
use
is
juice
juice
of
contains
lime
soaked
in
colourless
juice
is
juice
only
Vitamin
C
reactions
healing
organic
the
juice.
weakly
The
acid
that
acidic,
be
does
as
rust
reacts
can
it
such
of
citric
stains
with
the
removed
not
acid.
from
iron
by
‘burn’
A
household
clothes.
oxide
washing.
the
The
to
stain
form
Because
lime
clothes.
C
(ascorbic
in
of
acids
removal
compounds
Vitamin
body.
the
is
our
wounds
Citrus
vegetables
fruits
are
acid)
cells.
It
and
essential
an
as
limes,
sources
for
some
antioxidant
promotion
such
good
is
is
of
of
and
of
is
healthy
oranges
vitamin
and
the
chemical
essential
for
connective
lemons
the
tissue
and
raw
in
the
green
C.
Figure
7.4.3
Limes
in
Vitamin
C
is
easily
destroyed
by
oxidation.
This
oxidation
are
several
cultivated
areas
Caribbean.
increased
cooking
by
heating,
vegetables,
exposure
especially
to
air
above
and
pH
alkaline
7,
conditions.
reduces
the
So
amount
when
used
of
C
drastically.
Some
people
add
sodium
vegetables
when
cooking
them.
This
Sodium
improves
hydrogencarbonate
is
one
their
texture
the
vitamin
C
Determining
The
vitamin
compared.
the
and
C
content
the
of
method
1
Pipette
2
Add
a
1%
solution
when
known
DCPIP
in
vegetables
content
slightly
and
is
of
fruit
the
DCPIP
,
board
end
not
fade
point
is
volume
of
fruit
from
and
a
shake
reached
fruit
juice
amount
which
is
of
blue
can
when
C
uses
oxidised
juice
into
burette,
the
a
flask.
drop
fl ask
by
drop,
to
the
gently.
7.4.4
has
when
been
the
added
blue
to
colour
the
West
of
the
DCPIP
Indian
richest
YOU
Antacids
contain
bases
hydroxide
Sodium
such
to
as
magnesium
neutralise
hydrogencarbonate
decomposes
carbonate
toothpastes
excess
stomach
when
heated
foam
to
extinguishes
produce
carbon
Some
examples
carbonates
acid,
of
acids
lactic
in
acid,
living
citric
systems
acid
and
fires
because
it
abrasives
surface
dioxide.
are
methanoic
ascorbic
a
used
to
can
be
remove
used
rust
to
preserve
food
and
lime
of
under
6
The
the
C
in
fruit
the
excess
juice
can
be
layer
may
of
alkaline
vitamin
C
indicator
is
destroyed
by
teeth.
of
acid
in
as
the
These
also
reacting
the
heating
damage
enamel
Fluoride
vegetables
added
clean
acid,
stains.
and
are
help
side-effect
ions
toothpaste
Vitamin
that
to
mouth,
acid.
which
Vinegar
or
acid.
with
ethanoic
contain
and
have
5
known.
KNOW?
hydroxides
4
C
POINTS
magnesium
3
are
of
does
insoluble
2
cherries
source
solution.
Some
1
sailors
be
vitamin
DID
KEY
carried
prevent
scurvy.
vitamin
it
to
reduced.
flask
when
to
were
juice
the
The
continent
limes
alkaline.
Figure
3
were
cargoes
reduced.
unheated
determining
indicator
solution
the
C
heated
for
oxidation–reduction
colourless
the
vitamin
content
The
of
ships
and
getting
So
the
days
hydrogencarbonate
on
appearance.
the
transport
another,
to
In
sailing
to
from
vitamin
of
is
on
are
to
the
the
also
surface
teeth.
added
strengthen
to
the
and
enamel.
Some
scientists
that
fluoride
think
conditions.
content
DCPIP
.
of
fruit
juice
can
be
determined
using
the
some
the
of
the
ions
may
hydroxide
structure
of
the
replace
groups
in
tooth.
65
7.5
Solubility
salt
the
end
of
this
topic
salts
be
able
reaction
describe
solubility

describe
the
preparation
describe
the
by
by
describe
of
salts
the
by
hydrogen
It
is
YOU
preparation
replacing
ions
soluble
in
the
to
or
call
of
the
an
In
a
II
to
in
Even
water
.
quite
to
For
in
solid
is
mixed,
the
reaction.
salts
soluble
in
by
The
solid
precipitation
water
and
which
obtained
we
are
have
to
is
the
know
(solubility
rules)
are
insoluble.
given
in
T
able
Some
7.5.1.
rules
for
predicting
solubility
compounds
All
salts
of
All
nitrates
Group
and
I
Insoluble
compounds
elements
ammonium
salts
Chlorides,
bromides
and
iodides
chlorides,
bromides
and
iodides
silver
lead
Most
Sulfates
of
and
sulfates
and
Group
I
hydroxides
and
carbonates
Most
example,
of
calcium,
barium
lead
hydroxides
and
carbonates
I
and
II
oxides
react
with
water
Most
metal
oxides
say
that
it
is
salts
by
precipitation
on
the
obviously
that
low
soluble.
do
may
is
how
you
can
make
an
insoluble
salt,
for
example,
lead
chloride.
other
not
have
concentration
1
Identify
the
2
Identify
two
an
and
ions
sodium
present
soluble
in
salts
the
salt:
lead
containing
and
these
chloride.
ions,
e.g.
lead
nitrate
chloride.
of
3
Add
one
4
Filter
of
the
solutions
to
the
other.
solution.
off
water
EXAM

a
are
dissolves
We
dissolve
extremely
ions
If
soluble.
substances
appear
not.
hydroxides:
hydroxide,
is
make
solubility
Soluble
This
hand,
to
are
Some
Preparing
Barium
precipitation
decide
substance
hydroxide
sparingly
a
order
predicting
7.5.1
Group
slightly
are
compounds
acid.
difficult
insoluble.
Group
Calcium
others
soluble
KNOW?
sometimes
whether
but
two
of
Most
DID
of
of
combination
elements

water
precipitation
preparation
direct
called
compounds
for
T
able
salts
in
solutions
of
rules
salts
is
precipitate.
rules
which

soluble
when
to:

insoluble
are
you
obtained
should
rules
OUTCOMES
Many
At
and
preparation
Solubility
LEARNING
rules
Y
ou
the
in
the
and
precipitate,
dry
it
(Figure
then
wash
the
precipitate
with
distilled
7.5.1).
TIPS
need
to
know
so lubi
lity
order
to
rules
use
the
Sodium
chloride
appro
priate
me th
od
fo r
solution
mak
ing

When
a
salt.
Lead
mak
ing
a
nitrate
salt
solution
from
oxide,
a
me ta
l
or
remem
ber
me ta
l
that
We
the
me ta
l
shou
ld
be
or
in
me ta
l
oxide
add
to
lead
solution
and
chloride
The
nitrate
precipitate
that
stir
the
forms
is
of
lead
filtered
chloride
off
from
solution
7.5.1
Preparing
the
insoluble
salt
The
precipitate
washed
water
excess
.
Figure
66
sodium
solution
lead
chloride
with
and
is
distilled
dried
Preparing
We
can
react
a
react
two
metal
sodium
salts
2Na(s)
a
by
+
direct
elements
with
chloride
by
together
non-metallic
burning
Cl
(g)
combination
sodium
→
to
form
element.
in
a
For
salt.
T
o
do
example,
chlorine
gas
this
we
(Figure
we
can
usually
prepare
7.5.2).
2NaCl(s)
2
We
can
purify
Preparing
We
can
acids.
+
by
soluble
metal
Zn(s)
sodium
salts
make
The
the
ions
chloride
recrystallisation.
replacing
salts
by
replace
2HCl(aq)
by
reacting
the
→
hydrogen
metals
hydrogen
ZnCl
(aq)
+
H
2
CuO(s)
+
H
SO
2
The
1
method
Add
or
the
metal
2
Warm
3
Filter
of
→
metal
or
oxide
metal
should
flask
the
7.5.3)
gently
excess
metal
in
the
oxides
with
acid.
(g)
2
CuSO
(aq)
+
H
4
(Figure
the
off
the
(aq)
4
or
ions
ions
O(l)
2
is:
oxide
be
in
to
to
make
metal
the
acid
in
a
beaker.
The
metal
excess.
or
sure
metal
reaction
oxide.
is
The
complete.
filtrate
is
a
solution
Figure
salt.
7.5.2
When
sodium
chlorine,
4
Evaporate
point
is
the
evaporating
5
Filter
water
reached.
off
from
(Crystals
the
filtrate
start
to
until
form
on
the
crystallisation
the
side
of
can
the
the
the
6
Dry
the
of
crystals
crystals
and
wash
them
carefully
with
the
between
sheets
of
filter
1
paper.
2
Solubility
All
rules
3
copper
and
stir.
oxide
Warm
to
for
Group
are
acid
the
side
of
powder.
POINTS
nitrates
sulfuric
on
white
minimum
method
insoluble
a
water.
determining
Add
seen
as
in
chloride
basin.)
KEY
amount
be
jar
burns
sodium
I
Most
an
useful
salts
and
soluble
in
and
salt.
all
salts
water.
chlorides,
iodides
a
ammonium
in
for
appropriate
making
and
soluble
are
bromides,
sulfates
are
The solution turns blue as the reaction
gently
water.
occurs, showing that copper sulfate is
being formed
4
Many
oxides,
carbonates
5
Insoluble
by
6
filter
the
the
copper
Figure
We
can
using
a
reaction
solution
is
to
also
are
Many
soluble
by
prepared
reactions.
salts
the
can
be
reaction
of
complete,
remove
Evaporate
some
the
and
of
the
water
from
metals
or
metal
oxides
with
excess
filtrate
leave
to
crystallise
acids.
oxide
7.5.3
salts
and
insoluble.
precipitation
prepared
When
hydroxides
are
Making
make
titration
copper
soluble
method
sulfate
salts
(see
from
by
copper
reacting
oxide
an
acid
7
with
an
alkali
Some
salts
direct
reaction
with
a
can
be
of
made
a
by
metal
non-metal.
7.6).
67
7.6
Acid–base
Neutralisation
LEARNING
the
end
of
this
topic
reaction
be
able
between
an
acid
and
a
base
is
called
a
neutralisation
you
reaction.
should
reactions
OUTCOMES
The
At
titrations
The
products
are
a
salt
and
water.
For
example:
to:
KOH(aq)
+
HCl(aq)
→
KCl(aq)
+
H
O(l)
2

describe
neutralisation
reactions
using
We
indicators
a

describe
acid–base

describe
how
by
in
replacement
an
by
a
acid
prepare
of
directly
metal
or
a
hydrogen
or
been
1
The
2
As
univ
ersal
in
an
base
it
chan
ges
grad
ually
cann
ot
see
chan
ge
on
of
acid
the
indica
to r
tion
end
to
becaus
and
the
acid
is
blue-purple
added
blue-green
of
e
(pH
sharp
adding
to
an
which
acid
some
drop
by
universal
drop
to
indicator
as
the
start
(high
pH).
the
is
indicator
decreasing
colour
in
the
changes
alkaline
to
blue,
then
region).
the
acid
can
more
is
decreasing
use
a
substance
add
the
has
is
excess,
more
acid
in
an
is
called
a
indicator
added,
it
titration
given
to
volume
the
alkali
acid–base
completely
the
the
the
acid
gradually
use
reacted
of
neutralised
the
alkali,
the
indicator
changes
turns
red
from
(pH
yellow
is
below
7
further).
procedure
called
colour
completely
in
and
present
We
just
happens
the
alka
li
has
7).
and
acid
co lou
r
a
acid
(pH
as
We
you
end
indicator
determine
solution
until
the
indicator
with
point
to
of
of
the
the
suddenly
to
of
alkali
find
alkali.
The
titration.
At
the
amount
acid
has
out
or
alkali.
been
when
point
the
the
where
end
this
point,
changes.
dro p
at
If
point.
we
want
volume
1
of
to
2
Add
3
Fill
a
find
out
solution
Measure
into
Pipette
the
green
neutralised.
addi
ng
the
is
and
We
acid–
co lou
r
a
indicator
When
use
accu
rate
titra
by
added:
When
4
TIP
cann
ot
changes
hydroxide
technique.
is
Y
ou
pH
ion
3
EXAM
the
potassium
indirectly
ammonium
titration
how
of
salts
to
using
see
titrations
has
to
can
solution
a
known
titration
an
of
amount
volume
flask
indicator
the
potassium
using
of
a
solution
of
substance
hydroxide,
potassium
volumetric
to
the
hydroxide
pipette
alkali
present
in
in
a
given
we:
the
solution
(see
Figure
(alkali)
7.6.1).
flask.
filler
a
with
clean
a
burette
little
of
concentration
4
Set
up
the
burette
the
with
the
acid).
(amount
apparatus
acid
The
of
(after
acid
in
substance
shown
in
having
the
present
Figure
washed
burette
7.6.2
in
has
a
and
a
the
burette
known
given
volume).
record
the
initial
reading.
Volumetric
pipette
5
Slowly
all
6
the
When
final
add
the
time
the
to
indicator
burette
reading
acid
from
make
sure
changes
reading.
minus
the
the
This
initial
burette
that
is
the
colour
the
to
(the
rough
burette
the
contents
flask.
are
end
point),
titration.
reading
is
Swirl
the
flask
mixed.
The
called
record
fi nal
the
the
burette
titre
Solution
7
Repeat
point,
Figure
68
7.6.1
Filling
a
volumetric
pipette
steps
add
1
the
to
6
acid
but
this
drop
by
time
when
drop.
you
are
near
the
end
8
Repeat
the
process
until
you
have
two
titres
that
are
not
more
3
than
0.1 cm
apart.
Burette
Typical
T
able
results
are
shown
in
T
able
7.6.1.
7.6.1
Rough
1st
titre
titre
accurate
2nd
accurate
3rd
accurate
Acid
Final
burette
titre
titre
21.6
21.1
20.8
21.1
0.0
0.2
0.1
0.3
3
reading
Initial
(cm
)
burette
3
reading
(cm
)
Flask
3
Titre
(cm
21.7
)
20.9
20.7
20.8
Alkali
Preparing
soluble
salts
by
White
titration
Figure
We
can
make
a
soluble
salt
by
titrating
alkalis
such
as
Group
I
7.6.2
Titrating
tile
an
alkali
with
an
hydroxides
acid
or
an
aqueous
ammonia
indicator
,
acid
that
method
then
was
is
with
an
repeated
shown
especially
by
the
useful
acid.
The
without
titration
for
titration
the
to
making
is
indicator
,
just
first
carried
using
neutralise
ammonium
the
the
out
using
volume
alkali.
of
This
EXAM
When
2NH
(aq)
+
H
3
Figure
7.6.3
SO
2
shows
the
(aq)
→
(NH
4
)
4
SO
2
TIP
salts:
taking
(aq)
4
from
method.
bure tte
s
grad
uated
readi
ng
from
the
of
pipe tte
s,
shou
ld
be
bo tto
m
men
iscus
part
readi
ngs
and
(the
the
the
taken
of
the
conc
ave
surfac
e
of
the
so lutio
n).
KEY
1
You
the
put
the
flask
drops
of
alkali
with
a
in
2
few
You
add
burette
indicator
acid
until
changes
from
the
colour.
the
3
indicator
You
You
repeat
without
record
You
add
the
experiment
indicator
the
in
the
volume
of
1
flask.
POINTS
The
a
reaction
base
is
a
of
an
acid
with
neutralisation
acid
reaction.
the
volume
of
acid
added
you
recorded
in
step
2
2
The
or
an
3
concentration
alkali
An
indicator
end
base
You
allow
crystals
to
form.
4
You
put
the
The
then
filter
crystals
carefully
these.
can
then
washed
and
from
be
the
flask
evaporating
filter
dried
evaporate
paper
until
the
is
into
basin
7.6.3
Making
a
salt,
e.g.
is
used
of
an
to
show
acid–
the
A
titration
method
can
be
an
used
and
to
prepare
salts
of
water
I
metals
from
their
crystallisation
or
to
prepare
reached
ammonium
Figure
acid
using
titration.
point
hydroxides
point
an
titration.
Group
with
of
found
solution
4
You
be
acid–base
the
5
can
ammonium
sulfate,
using
a
titration
salts.
method
69
7.7
Neutralisation,
salts
and
solution
concentration
Thermometric
LEARNING
When
At
the
end
of
this
topic
be
able
an
the
describe
using

list
temperature
the
uses
and
reactions
a
changes
dangers
acid
of
when
we
known
alkali,
can
energy
use
the
is
released.
change
in
This
energy
temperature
heats
of
a
add
an
acid
titration.
to
is
an
alkali
needed
The
to
to
determine
neutralise
procedure
is
an
shown
what
volume
alkali.
in
This
Figure
is
of
called
7.7.1(a):
of
Place
a
measured
volume
of
alkali
in
an
insulated
container
e.g.
a
salts
polystyrene
define
an
We
concentration
thermometric
1

mixture.
to:
neutralisation
particular
neutralises
reaction
solution

acid
you
up
should
titrations
OUTCOMES
the
terms
concentration
drinking
cup.
molar
and
2
Record
3
Add
the
initial
temperature
of
the
alkali.
mass
concentration.
acid
of
measured
a
4
After
each
record
Acid
in
burette
The
end
alkali,
is
its
known
concentration
from
a
burette
in
small
amounts.
addition
of
acid,
stir
the
solution
in
the
cup
and
temperature.
point
of
shown
the
by
reaction,
the
break
when
in
the
the
acid
curve
of
has
a
just
graph
neutralised
of
the
temperature
Thermometer
against
volume
of
acid
added
(Figure
7.7.1(b)).
Stirrer
The
In
uses
7.4
we
baking
some
learned
powder.
Calcium
Polystyrene
of
salts
about
Many
carbonate
is
the
use
other
used
of
salts
to
sodium
have
make
hydrogencarbonate
particular
cement.
in
uses:
Limestone
rock
(which
Alkali
cup
is
b
calcium
then
mixed
) C° (
Calcium
erutarepmeT
bones,
End
carbonate)
with
sulfate
teeth
is
mixed
calcium
is
and
also
sulfate
used
nails.
with
It
is
as
and
a
also
clay
and
the
food
used
heated
mixture
additive
to
make
to
is
in
a
furnace.
It
is
crushed.
promote
plaster
of
healthy
Paris.
point
This
can
be
used
Magnesium
skin.
It
can
to
make
sulfate
also
be
casts
(Epsom
used
as
to
salts)
a
keep
is
broken
used
in
bones
bath
salts
in
to
place.
refresh
the
laxative.
3
Volume
Figure
7.7.1
a
of
acid
added
Apparatus
(cm
)
Some

Sodium
graph
of
Sodium
help

chloride
is
nitrate
Sodium
used
preservation:
to
preserve
present
Molar
used
and
the
benzoate
It
reduces
Solution
foods
is
often
maintain
foods.
Some
food
by
food.
osmosis.
It
withdraws
Brine
(a
water
solution
in
sodium
colour
is
used
nitrite
of
the
as
bacterial
a
are
used
preservative
and
to
preserve
meats
fungal
in
fruit
growth
juices
below
and
pH
to
acidic
5.
concentration
concentration
solvent
and
food.
is
the
number
of
moles
of
units
are
solute
dissolved
3
preservatives
from
sodium
pickling.
containing
a
70
of
results

7.7.2
in
microorganisms
chloride)
Figure
used
titration,
any
typical
are
for
thermometric
b
salts
make
1 dm
−3
of
a
solution.
Its
mol dm
in
number
of
moles
of
solute
(mol)
–3
concentration
(mol dm
)
DID
=
YOU
KNOW?
3
volume
of
solution
(dm
)
Thermometric
In
calculations
involving
solutions
we
also
need
to
be

to
change
mass
in
grams
3

to
change
to
in
moles
3
cm
to
by
dividing
the
volume
in
cm
used
by
for
solution
use
3
dm
titrations
can
remember:
an
many
reactions
where
indicator
,
you
for
cannot
example,
1000
displacement
reactions
and
−3

that
moles
of
solute
(mol)
=
concentration
(mol dm
)
×
volume
oxidation–reduction
reactions.
3
(dm
).
The
method
there
Worked
example
is
the
works
large
best
when
temperature
1
change
Calculate
a
concentration
of
a
solution
of
sodium
in
the
reaction
mixture.
hydroxide
3
(M
=
40)
containing
0.60 g
NaOH
in
200 cm
solution.
r
0.60
1
Convert
grams
to
moles:
=
0.015 mol
DID
40
3
2
Change
3
cm
to
dm
3
:
YOU
KNOW?
3
200 cm
=
0.20 dm
Many
the
people
use
of
are
worried
sodium
nitrate
about
as
0.015
–3
3
Calculate
concentration:
=
0.075 mol dm
a
food
preservative.
It
breaks
0.20
down
small
Worked
example
in
the
packaging
amounts
of
to
form
chemicals
2
called
nitrosamines.
These
have
3
Calculate
the
mass
of
calcium
chloride
(M
=
111)
in
50 cm
of
a
r
been
shown
to
cause
cancer
,
−3
0.20 mol dm
solution
3
1
Change
cm
of
calcium
3
to
dm
chloride.
3
:
50 cm
and
infants
3
=
may
damage
and
Calculate
3
Convert
number
moles
to
of
moles:
grams:
0.20
0.01
hasten
brains
the
onset
of
of
0.050 dm
Alzheimer’s
2
the
×
×
0.05
111
=
=
disease.
0.01 mol
1.1 g
(to
2
significant
figures)
Mass
concentration
EXAM
We
can
also
express
concentrations
concentration
is
solvent
1 dm
the
number
of
in
terms
grams
of
of
mass.
solute
dissolved
3
to
make
concentration
in
T
he
a
a
solution.
of
Its
units
solute
are
g dm
may
how
(g)
of
solution
(dm
)
the
POINTS
mole
s
end
point
thermometric
2
Sodium
trian
gle
you
find
remem
ber
concen
tratio
n.
of
a
neutralisation
reaction
can
be
found
by
the
mole
s
equat
ion
and
The
to
Cover
3
1
help
=
volume
KEY
follow
ing
−3
of
mass
mass
TIP
Mass
from
for
to
show
findin
g
concen
tratio
n
volum
e.
a
titration.
nitrate,
sodium
benzoate
and
sodium
chloride
are
Moles
used
to
preserve
foods.
÷
3
Sodium
nitrate
decomposes
harmful
to
4
Calcium
carbonate
5
Magnesium
(plaster
6
Molar
of
infants
or
is
sulfate
Paris)
is
are
is
concentration
used
is
form
substances
that
may
be
in
the
to
in
make
bath
casts
÷
Conc
(mol dm
carcinogenic.
used
used
to
Volum
–3
)
e
×
3
(dm
)
cement.
salts
for
number
and
broken
of
calcium
sulfate
limbs.
moles
of
solute
3
dissolved
in
a
solvent
to
make
1 dm
of
solution.
71
7.8
Solution
and
Making
LEARNING
At
the
end
should
be
know
of
this
able
how
standard
topic
define
a
standard
solution
We
need
has
the
to
correct
sure
that
the
concentration
acid
by
(or
alkali)
titrating
it
we
with
use
a
in
the
primary
burette
standard.
to:
to
prepare
a
solution
the
make
you
standard
term
solution
specified
temperature
standard
conditions
glassware

titrations
OUTCOMES
A

concentration
is
has
a
and
are
calibrated
known
25 ºC
at
accurate
pressure
and
20 ºC.
(usually
concentration
at
s.t.p.).
1 atmosphere
For
accurate
pressure,
work
in
at
a
Although
most
many
branches
standard
of
chemistry
a
standard
concentration
contains
one
mole
of
concentration
3
substance

perform
calculations
analysis
data,
type
of
titration
of
solution
under
standard
conditions.
This
standard
solution
used
in
electrochemistry.
We
is
can
form
e.g.
solutions
from
1 dm
using
the
volumetric
in
of
other
concentrations
by
diluting
the
standard.
results
3
To

perform
calculations
make
200 cm
concentration
titration
results
number
of
mole
ratio
mass
and
in
the
molar
concentrations
Weigh
out
of
into
make
the
2
Add
3
Wash
4
KNOW?
to
a
primary
substance
be
purity,
form
a
to
a
give
a
the
hydroxide
(see
Figure
of
known
7.8.1):
required
amount
of
sodium
hydroxide
and
tip
the
beaker.
enough
out
Wash
be
very
stable
5
able
Fill
high
water
to
dissolve
the
sodium
hydroxide.
the
from
out
the
volumetric
flask
the
into
beaker
beaker
through
several
the
with
the
times
funnel
to
pure
flask,
with
the
water
using
pure
then
a
pour
the
funnel.
water
and
add
the
flask.
the
volumetric
the
meniscus
Put
the
is
flask
on
the
with
pure
calibration
water
so
that
the
bottom
of
mark.
solution
6
and
flask
standard,
should
obtained
sodium
and
washings
T
o
of
volumetric
the
solution
YOU
solution
a
the
reactants.
DID
a
use
reacting,
solid
equation
we
involving
moles
1
the
of
from
reproducible
results
stopper
on
the
flask
and
shake
the
fl ask
gently.
in
titration.
Calculations
In
Ground
every
titration
from
titration
calculation
we
results
need
to
know
four
of
the
following
glass
five
points:
stopper

the
balanced
equation
for

the
concentration
of

the
volume
titre

the
concentration
of

the
volume
solution
the
the
reaction
solution
in
the
burette
solution
in
the
titration
Mensicus
Calibration
of
the
mark
In
of
titration
solution
Example
of
the
calculations
in
the
the
we
titration
in
the
usually
titration
need
to
flask
flask.
deduce
the
concentration
flask.
1
3
200 cm
3
20 °C
25.0 cm
of
potassium
of
sulfuric
hydroxide
solution
is
exactly
neutralised
3
12.3 cm
by
−3
acid
of
concentration
0.200 mol dm
.
Calculate
−3
Figure
7.8.1
A
volumetric
used
to
flask
make
solutions.
is
the
concentration,
in
mol dm
2KOH(aq)
+
H
SO
2
72
of
the
potassium
hydroxide
standard
(aq)
4
→
K
SO
2
(aq)
4
+
2H
O(l)
2
solution.
We
1
use
the
following
Calculate
the
procedure:
number
concentration
and
of
moles
volume
are
of
reagent
known.
for
This
is
which
the
both
acid.
−3
moles
(mol)
moles
acid
=
concentration
(mol dm
3
)
×
volume
(dm
)
12.3
–3
=
0.200
×
=
2.46
×
10
mol
1000
2
Use
the
mole
number
2 mol
of
KOH
ratio
moles
:
in
of
1 mol
the
balanced
equation
to
calculate
H
SO
2
4
−3
So
3
moles
KOH
Calculate
the
=
2
the
KOH.
×
2.46
×
concentration
−3
10
of
=
KOH
4.92
×
10
mol
KOH
using:
number
of
moles
of
solute
(mol)
−3
concentration
(mol dm
)
=
–3
volume
of
solution
(dm
)
Figure
7.8.2
The
results
can
be
from
a
titration
1000
−3
concentration
of
KOH
=
4.92
×
10
−3
×
=
0.197 mol dm
25.0
the
The
acid
equation
or
of
an
alkali.
for
the
reaction
of
calcium
hydroxide
with
hydrochloric
is:
Ca(OH)
(aq)
+
2HCl(aq)
→
CaCl
2
(aq)
+
2H
2
of
calcium
hydroxide
(M
=
74.0)
TIP
O(l)
2
When
0.148 g
was
completely
dissolved
carryi
ng
calcu
lations
r
water.
Calculate
the
volume
of
0.150 mol dm
hydrochloric
to
just
Calculate
neutralise
the
moles
of
the
calcium
calcium
mole
acid
conc
entra
tions
,
required
out
invo lv
ing
−3
1
calculate
2
EXAM
in
to
concentration
acid
Example
used
remem
ber
hydroxide.
hydroxide:
the
units
are
usin
g
the
0.148
of
vo lum
e
you
throug
hout
calcu
lation
–
you
–3
=
2.00
×
10
mol
Ca(OH)
may
2
need
to
74.0
Use
the
mole
ratio
in
the
balanced
equation
to
calculate
dm
of
moles
of
Ca(OH)
:
2 mol
HCl
−3
3
moles
Calculate
HCl
the
=
2
an
that
appro
priate
the
×
(2
volume
×
of
10
HCl
number
units
conc
entra
tion
mol dm
2
So
so
acid:
of
1 mol
at
the
point
number
3
cm
3
to
2
conv
ert
are
−3
−3
)
=
4.00
×
10
mol
HCl
using:
of
moles
of
solute
(mol)
3
volume
(dm
)
=
–3
concentration
of
solution
(mol dm
)
−3
4.0
×
10
3
volume
of
HCl
=
=
0.0267 dm
0.150
KEY
1
POINTS
A
standard
out
to
a
a
fixed
fixed
solution
amount
volume
in
is
of
a
prepared
solid
and
by
weighing
making
volumetric
it
up
flask.
3
The
Standard
concentration
refers
to
one
from
relationship
of
2
concentration
found
moles
the
of
an
results
between
reacting
acid
of
a
or
alkali
titration
concentration,
and
volume
of
can
using
be
the
number
solution
in
mole
3
dm
,
as
well
as
the
mole
ratio
in
the
equation
3
of
substance
in
1 dm
of
solution
under
for
standard
the
reaction.
conditions.
73
8
Oxidation
and
reduction
reactions
8.1
Oxidation
What
LEARNING
the
end
should

be
identify
of
this
able
topic
loss
or
definitions

Oxidation
is

Reduction
of
the
is
in
terms
gain,
or
When
copper
oxidation
gain
the
of
loss
reduction
oxide
and
reduction
of
oxygen
by
oxygen
by
a
a
are
reacts
occurring
at
with
from
oxidation
substance.
the
same
both
oxidation
and
time:
+
H
(g)
→
Cu(s)
+
H

formulae.

Hydrogen
the
Copper
copper

is
oxide
Oxidation
called
been
losing
has
oxygen
been
oxidation
can
transfer
extend
that

Oxidation

Reduction
our
do
is
loss
is
of
gain
to
have
and
in
the
the
copper
hydrogen.
occurred
involve
at
reduction
reactions
redox
definition
not
from
oxide.
We
say
We
say
that
the
reduced.
reduction
where
atoms
oxidised.
of
the
occur
or
same
at
redox
the
time.
same
time
are
reactions.
reactions
oxidation
and
reduction
to
include
oxygen:
electrons.
of
electrons.
oxidation–reduction
reaction
jet
oxygen
has
oxidation–reduction
reactions
An
is
and
Electron
We
gaining
hydrogen
oxide
Reactions
8.1.1
O(l)
2
number
that
Figure
substance.
hydrogen
2
deduce
are:
transfer
CuO(s)

reactions?
and
reactions
oxygen
electrons
oxidation–reduction
you
to:
oxidation
reduction
of
reduction
OUTCOMES
Simple
At
are
and
fuel
takes
place
when
Magnesium
reacts
magnesium
chloride:
with
chlorine
to
form
the
ionic
compound
burns.
Mg(s)
+
Cl
(g)
→
MgCl
2

Each
been
magnesium
oxidised
to
(s)
2
atom
loses
two
magnesium
electrons.
Magnesium
atoms
have
ions:
2+
Mg

Each
chlorine
Chlorine
DID
YOU
has
atom
been
→
in
the
Mg
+
chlorine
reduced
to
2e
molecule
chloride
gains
one
electron.
ions:
KNOW?
−
Cl
+
2e
→
2Cl
2
We
and
can
also
define
reduction
hydrogen
loss
hydrogen
is
in
oxidation
terms
or
gain.
reduction
of
Gain
and
of
Equations
like
this
separately
are
called
hydrogen
is
oxidation.
in
the
is
especially
chemistry
of
the
oxidation
and
reduction
reactions
equations
example
is
the
displacement
reaction:
This
Cl
definition
half
loss
Another
of
showing
useful
(aq)
+
2I
(aq)
→
2Cl
(aq)
2
+
I
(aq)
2
organic

Chlorine
has
gained
electrons
from
iodine.
Chlorine
has
been
reduced.
compounds.
Reduction:
Cl
+
2
74
2e
→
2Cl
Oxidation:
2I
→
I
+
2
2e
Oxidation
We
can
redox
numbers
extend
our
reactions
oxidation
(oxidation
definition
involving
of
states)
oxidation
covalent
and
reduction
compounds.
We
do
to
this
include
by
EXAM
T
he
numbers.
wo rd
s
help
An
oxidation
number
(abbreviation
OxNo)
is
a
number
TIP
using
given
you
to
electro
n
each
atom
or
ion
in
a
compound
to
show
the
degree
of
OIL
trans
fer
oxidation.
react
ions.
There
are
rules
for
applying
oxidation
1
OxNo
refers
to
a
single
atom
or
ion
in
a
and
The
Cl
OxNo
=
0,
of
Zn
each
=
atom
in
an
element
in
redox
Redu
ction
Is
Is
compound.
Gain
2
will
Oxid
ation
numbers:
Loss
RIG
remem
ber
is
0,
e.g.
each
Cl
(of
electro
ns).
in
0.
2
3
The
OxNo
of
an
ion
arising
from
a
single
2−
ion,
e.g.
Cl
=
−1,
O
atom
=
charge
=
+3.
on
the
2+
=
−2,
Mg
=
+2,
Al
DID
4
The
OxNo
of
an
oxygen
atom
in
a
compound
is
−2
(but
YOU
KNOW?
in
Oxidation
peroxides,
it
is
on
5
The
OxNo
of
number
a
hydrogen
atom
in
a
compound
is
+1
but
a
property
called
with
a
metal
alone,
it
is
−1,
e.g.
in
HCl,
NH
SO
2
,
H
=
+1
but
in
CaH
4
,
H
=
If
we
ignore
The
elements,
2
sum
of
all
the
OxNos
of
atoms
or
ions
in
a
compound
e.g.
in
Al
O
2
a
period
down
a
:
in
the
periodic
table.
2−
=
2
×
(+3)
=
+6
a nd
3O
=
3
×
(−2)
=
−6
The
2−
The
0
3
3+
7
element.
Group
electronegativity
across
decreases
group
2Al
the
is
and
zero,
an
−1.
increases
6
of
and
3
H
the
when
electronegativity
combined
depends
−1).
sum
of
the
OxNos
in
a
compound
ion
such
as
SO
most
element
or
electronegative
is
fluorine.
The
more
4
NO
=
the
charge
on
the
ion,
e.g.
sum
of
oxidation
number
of
electronegative
element
given
negative
is
3
2−
S
+
4O
in
SO
=
−2.
the
more
(or
less
4
positive)
in
Applying
oxidation
number
rules
to
the
atoms
elements
the
of
many
have
OxNos
we
elements
variable
in
OxNos.
Groups
So
we
IV
,
V
have
and
to
VI
work
and
−1
and
out,
is
F
has
the
+1.
know.
1
1
the
Cl
using
POINTS
Oxidation
oxygen
Deduce
ClF
,
So
transition
these
KEY
Example
compound
number
.
compounds
OxNo
The
oxidation
OxNo
of
Fe
in
the
ionic
compound,
is
or
addition
loss
of
of
electrons.
FeCl
3
2
−

Applying
rule
3:
Cl
=

Applying
rule
6:
Fe
−1
so
3Cl
=
Reduction
or
+
(−3)
=
0
So
is
loss
of
oxygen
−3
OxNo
of
Fe
in
FeCl
=
gain
of
electrons.
+3.
3
3
Example
In
an
reaction
2
both
Deduce
oxidation–reduction
the
OxNo
of
S
in
H
rules

Applying
rule
4
and
5:
O
=
−2
and
H
=
S
+
4O
the
Oxidation
=
0
So
2
×
(+1)
+
S
+
4
×
(−2)
=
us
So
2H
sum
+
of
4O
OxNos
=
time.
number
the
+2
of
+
(−8)
atom
=
−6
So
OxNo
of
S
=
degree
(OxNo)
of
0
oxidation

same
6:
tells
+
at
+1
4
2H
reduction
4
occur
Applying
reaction)
and
SO
2

(redox
oxidation
or
or
ion
reduction
in
a
of
an
compound.
+6.
5
Oxidation
allow
us
to
oxidation
or
ions
number
deduce
number
that
rules
are
the
of
atoms
variable.
75
8.2
Oxidising
and
reducing
Changes
LEARNING
the
end
of
this
topic

be
identify
able
reduction

and
reduction
atom
between
reducing

Oxidation
is

Reduction
an
is
a
number
oxidising
When
describe
be
defined
during
increase
in
a
in
terms
of
changes
of
OxNo
reaction.
oxidation
decrease
in
oxidation
tin
reacts
with
nitric
acid,
+
4HNO
of
number.
the
oxidation
(aq)
→
SnO
3
OxNos
that
number.
numbers
change
as
reduction
agents
examples
compounds
can
ion
shown:
Sn(s)

or
from
oxidation
distinguish
and
specific
and
reactions
in
a
to:
oxidation
changes
number
you
of
should
oxidation
OUTCOMES
Oxidation
At
in
agents
can
act
0
(s)
+
4NO
2
+5
(g) +
2H
2
+4
O(l)
2
+4
as
oxidation
both
an
oxidising
reducing
agent
and
a
agent.
The
tin
(Sn)
The
nitric
is
oxidised
acid
(HNO
)
because
gets
its
OxNo
reduced
increases
because
the
from
OxNo
0
of
to
+4.
the
N
3
decreases
When
EXAM
from
copper
+5
to
oxide
+4.
reacts
with
ammonia,
the
oxidation
changes
are:
TIP
reduction
When
iden
tifyi
ng
atom
s
ge ts
reduc
ed,
chan
ge
the
in
num
ber
.
as
bo th
chan
ge
H
or
the
+
N
(g)
+
3H
2
0
O(l)
2
0
which
The
copper
is
reduced
The
ammonia
because
its
OxNo
decreases
from
+2
to
0.
2
and
and
Atoms
)
or
from
−3
gets
to
oxidised
because
the
OxNo
of
the
N
ions
with
0.
variable
OxNos
exist
in
different
oxidation
3+
usua
lly
they
do
For
example,
Fe
states.
2+
has
a
higher
oxidation
state
than
Fe
.
if
react
ants
For
(NH
3
increases
oxidat
ion
But
are
produc
ts.
3Cu(s)
and
compo
unds
no t
their
O
2
→
to
atom
s
in
do
num
bers.
(g)
−3
oxidat
ion
react
ants
produc
ts
2NH
+2
oxidation
need
Oxyg
en
hydr
ogen
+
3
OxNos
oxidis
ed
you
iden
tify
3CuO(s)
which
exam
ple
or
in
react
ion :
CuO
+
H
→
2
Cu
+
H
O
2
oxyg
en
in
OxN
still
H
2
in
is
does
o
a
no t
becaus
e
chan
ge
it
is
compo
und
but
oxidis
ed.
Figure
8.2.1
Some
sunglasses
involving
76
silver
get
ions.
darker
or
lighter
because
of
redox
reactions
Oxidising
During

An
of
a
and
agents
EXAM
reaction:
oxidising
a
reducing
agent
particular
atom
gains
or
electrons
ion
in
the
and
gets
oxidising
reduced.
agent
The
OxNo
An
A
a
reducing
particular
agent
atom
loses
or
ion
electrons
in
the
and
gets
reducing
oxidised.
agent
The
OxNo
of
the
reaction
between
aqueous
chlorine
and
from
less
increa
se
a
can
nega
tive
nega
tive
to
OxN
o
a
or
increases.
to
In
OxN
o
decreases.
be

TIP
aqueous
0.
For
exam
ple,
in
the
react
ion :
potassium
bromide:
Cl
+
2
Cl
(aq)
+
2KBr(aq)
→
Br
2
OxNos
(aq)
+
equation:
−1
Cl
2Cl
0
(aq)
+
2Br
(aq)
→
bromide
electron
ion
and
its
the
OxNo
reducing
increases
agent
from
(aq)
because
−1
+
2Cl
(aq)
to
each
ion
loses
ions
an
is
an
oxidising
agent
because
−1
are
chan
ge
to
0,
so
in
OxN
o
brom
ide
oxidis
ed.
0.
2
Chlorine
ions
from
Cl

Br
2
2
is
+
−1
Br
2
The
→
2
0
Br
Ionic
2Br
2KCl(aq)
each
chlorine
atom
gains
an
chan
ges
from
0
to
in
−1,
OxN
o
so
Cl
is
2
electron
In
the
(H
O
2
and
the
reaction
)
in
acid
OxNo
between
decreases
from
potassium
0
iodide
to
−1.
and
reduc
ed.
hydrogen
peroxide
solution:
2
2KI(aq)
+
H
O
2
−1
(aq)
+
H
2
SO
2
(aq)
→
I
4
(aq)
+
K
2
−1
SO
2
(aq)
+
2H
4
O(l)
2
0
−2
OxNos
+
Ionic
equation:
2I
(aq)
+
H
O
2

Potassium
its
OxNo
iodide
is
increases
a
(aq)
2H
(aq)
→
I
−1
(aq)
+
2H
2
reducing
from
+
2
to
agent
because
it
O(l)
2
loses
electrons
and
0.
DID

Hydrogen
and
the
peroxide
OxNo
of
is
an
oxidising
oxygen
agent
decreases
because
from
−1
to
it
gains
−2
(see
YOU
rule
4
in
8.1).
Some
and
Some
compounds
can
act
as
both
oxidising
and
reducing
compounds
reduce
to
the
have
how
nature
of
the
other
reactants
and
conditions.
hydrogen
peroxide
oxidises
iodide
ions
to
peroxide
also
reduces
chlorine
to
chloride
(aq)
+
H
2
OxNos
The
is
0
chlorine
oxidised
KEY
1
is
(aq)
→
2HCl(aq)
because
the
+
O
2
−1
because
OxNo
of
its
OxNo
the
O
When
reacts
with
dilute
sodium
chloride
hydroxide,
ions,
Cl
it
(OxNo
−1)
(OxNo
and
of
Cl
chlorate( )
=
ions,
ClO
+1).
0
decreases
atoms
0)
(g)
2
−1
reduced
and
the
peroxide
increases.
POINTS
Increase
in
oxidation
2
O
2
=
ions:
=
Cl
(OxNo
iodine.
forms
Hydrogen
oxidise
We
cold
seen
can
themselves.
agents
chlorine
according
KNOW?
electrons
An
oxidation
number
oxidising
is
agent
number
is
oxidation
and
decrease
in
reduction.
gains
electrons
and
gets
reduced
in
a
reaction.
3
A
reducing
4
Hydrogen
reducing
agent
loses
peroxide
agent
electrons
can
act
depending
as
on
and
an
gets
oxidised
oxidising
the
other
agent
in
a
or
reaction.
a
reactant.
77
8.3
Using
oxidising
reducing
T
ests
LEARNING
the
end
oxidising
of
this
topic
be
for
able
common
describe
tests
oxidising
for
and
common
reducing
tests
sulfuric
describe
the
action
and
change
reducing
in
the
agents
solution
involve
under
the
test.
Many
of
oxidising
agents
are
the
test
added
to
solution
the
to
be
reaction
acidic,
mixture
so
a
when
few
drops
of
appropriate.
iodide
is
a
reducing
agent
that
is
used
to
test
for
oxidising
of
When
potassium
iodide
is
added
to
an
acidified
solution
of
and
an
reducing
oxidising
colour
agents
agents.
common
a
require
acid
Potassium

of
to:
these

agents
you
observation
should
agents
OUTCOMES
Tests
At
for
and
in
oxidising
agent
such
as
hydrogen
peroxide,
aqueous
chlorine
or
everyday
potassium
manganate( VII),
the
solution
turns
brown
because
iodine
is
activities.
formed.
colour
T
able
EXAM
T
able
8.3.1
for
Tests
below
two
for
shows
the
compounds
oxidising
oxidation
used
to
number
test
for
changes
oxidising
and
agents.
agents
TIP
Reducing
When
8.3.1
changes
usin
g
sulfa
te
to
(in
acidic
agent
used
Oxidation
solution)
number
Colour
change
changes
iron(
II)
test
Potassium
fo r
iodide
I
(−1)
→
I
Colourless
(0)
(I
)
to
2
oxidis
ing
co lou
r
agen
ts,
chan
ge
(I
ion)
brown
(I
the
from
)
2
2+
Iron(II)
sulfate
Fe
2+
3+
(+2)
→
Fe
Pale
(+3)
green
(Fe
)
2+
Fe
(aq)
no t
3+
to
Fe
obviou
s
so lutio
ns.
mak
e
add
this
excess
hydr
oxide.
2+
(aq)
is
(Fe
ion)
to
yellow-brown
3+
in
In
(Fe
dilute
order
more
to
obviou
s,
T
ests
sodium
T
his
rust-c
o loured
)
gives
a
precip
itate
for
Potassium
for
reducing
agents
manganate( VII)
reducing
agents.
is
When
an
oxidising
acidified
agent
potassium
that
is
used
to
test
manganate( VII)
is
3+
if
Fe
(see
ions
are
presen
t
19.1).
added
(Na
to
SO
2
)
a
colour
T
able
YOU
such
peroxide,
as
its
zinc,
iron( II)
colour
sulfate,
changes
sodium
from
purple
sulfite
to
T
able
changes
8.3.2
8.3.2
for
Tests
shows
two
for
the
oxidation
compounds
reducing
used
number
to
test
for
changes
and
reducing
agents.
agents
KNOW?
Oxidising
Breathalysers
to
detect
level
in
breath
agent
used
Oxidation
number
Colour
change
the
(in
alcohol
agent
hydrogen
3
colourless.
DID
reducing
or
acidic
solution)
changes
formerly
−
Potassium
used
potassium
MnO
−
(Mn
=
+7)
Purple
(MnO
4
dichromate(VI)
4
2+
manganate(VII)
to
determine
the
amount
→
Mn
(+2)
ion)
−
(MnO
alcohol
in
the
breath.
alcohol
in
the
breath
orange
(Mn
reduced
dichromate(VI)
the
green
Cr
ion.
ion
2−
Potassium
Cr
O
Modern
system
in
78
the
to
use
an
monitor
breath
electronic
alcohol
accurately.
levels
2−
(Cr
=
+6)
Orange
(Cr
7
O
2
3+
dichromate(VI)
2−
(Cr
O
2
breathlysers
)
4
The
3+
to
colourless
2+
ion)
2
the
to
of
ion)
7
→
Cr
)
7
3+
(+3)
to
green
(Cr
)
Oxidation
and
reduction
Oxidation–reduction
life.
For
example,
hydrated
year.
The
For
iron
Bleaches
contain
bleach
added
to
the
The
with
an
important
rusting
many
(the
rusting
life
part
oxidation
economies
about
clothes
chlorate( )
out.
reaction
play
of
everyday
millions
see
in
everyday
of
of
iron
to
pounds
form
every
15.6.
bleach
oxidises
washed
cost
information
of
are
the
effects
oxide),
more
action
reactions
the
in
ion
stain
or
remove
).
dye
chlorate( )
the
to
(ClO
When
to
ion
a
stains.
added
colourless
behaves
as
an
Many
to
bleaches
stained
form
cloth,
which
oxidising
is
the
then
agent
in
this
dye:
Figure
coloured
dye
(reduced
form)
Sulfites
and
Many
such
+
ions
→
colourless
(oxidised
sulfur
bacteria
as
chlorate( )
and
sodium
dioxide
fungi
in
need
food
oxygen
hydrogensulfite
dye
+
chloride
8.3.1
ions
Ships’
the
and
form)
hulls
rust
presence
easily
of
in
water
air.
preservation
to
(NaHSO
survive
)
are
and
multiply.
reducing
Sulfites
agents.
They
3
prevent
the
preventing
prevent
of
oxidation
fats
squashes
prevent
growth
from
to
the
microbes
and
getting
prevent
ethanol
in
foods
inhibiting
rancid.
bacterial
oxidising
enzyme
Sulfur
action.
to
such
It
as
action.
dioxide
is
ethanoic
fish
also
is
and
fruit
Sulfites
added
added
to
by
also
to
fruit
wine
to
DID
YOU
KNOW?
acid.
Y
ou
must
take
great
chlorate-containing
Browning
of
of
cut
fruits
is
caused
by
oxidation
reactions.
In
of
oxygen,
enzymes
in
the
broken
cells
change
colour
molecules
called
phenols
to
polymers
(see
14.2)
which
KEY
1
Sulfites
3
Potassium
Potassium
used
to
Tests
for
iodide
oxidation
Bleaches
Sulfites
the
or
iron( II)
dichromate( VI)
test
for
reducing
oxidising
of
are
colourless
5
this
by
inhibiting
dyes
They
used
may
enzyme
attack
fibres
such
as
nylon,
and
wool,
causing
holes.
action.
sulfate
are
used
to
test
for
agents.
observation
4
prevent
garments.
POINTS
oxidising
2
bleaches.
the
are
silk
coloured.
oxidise
small
also
colourless
may
the
to
presence
with
fruits
They
Browning
care
oxidising
potassium
manganate( VII)
are
reducing
colour
agents
agents
depend
on
the
changes.
that
oxidise
stains
to
a
form.
and
sulfur
oxidation
oxidation
and
specific
or
agents.
of
dioxide
foods
are
such
reducing
as
fish
and
agents.
fruit
by
They
prevent
preventing
reactions.
79
9
Electrochemistry
9.1
Conductors
and
insulators
Conductors
LEARNING
Conductors
At
the
end
of
this
topic
be
able
describe
leading
of
are
substances
electricity.
They
that
allow
have
an
a
low
electric
resistance
current
to
to
the
pass
through
to:
them

insulators
you
passage
should
and
OUTCOMES
easily.
They
can
be:
investigations
to
the
substances
as
classification
conductors

solids,
e.g.

liquids,

solutions,
metals
or
graphite
of
e.g.
molten
zinc
chloride
or
molten
metals
or
non-conductors
e.g.
a
solution
of
sodium
chloride
in
water
or
solutions
of
acids.

distinguish
and

between
electrolytic
classify
strong
electrolytes
or
weak
metallic
conduction
as
based
on
conductivity.
Figure
9.1.1
Overhead
that
are
power
good
lines
are
conductors
made
of
of
metals
electricity.
a
Insulators
electricity.
A
Ammeter
resist
Most
the
flow
of
insulators
electricity.
used
to
They
prevent
are
the
poor
flow
conductors
of
electricity
of
are
Lamp
solids
Crocodile
e.g.
plastics
or
ceramics.
clip
We
can
using
test
one
to
or
see
whether
other
of
the
a
substance
circuits
is
shown
a
in
conductor
Figure
or
insulator
by
9.1.2.
Metal

b
a.c.
If
the
substance
Conductivity
source
lamp
meter

Solution
Inert
under
will
a
If
substance
the
show

(bulb)
show
lamp
The
will
a
9.1.2
Circuit
the
a
is
to
test
conductivity
of
solids.
circuit
b
a
not
between
crocodile
switch
is
clips
is
closed.
a
conductor
The
ammeter
the
will
light
when
the
the
crocodile
switch
is
clips
is
closed.
an
insulator,
The
the
ammeter
will
not
reading.
higher
the
ammeter
Metallic
and

conduction
Metallic
potential
reading,
the
better
the
conductor
is.
electrolytic
is
due
conduction
to
the
movement
of
mobile
used
solutions.
electrons
difference
move.
They
is
through
applied.
remain
the
The
metal
metal
lattice
atoms
(see
in
5.6)
the
when
lattice
a
do
unchanged.
conductivity

is
conductivity
or
the
electrodes
used
meter
80
between
when
test
not
In
light
reading.
(delocalised)
Figure
placed
power
to
of
test
Electrolytic
conduction
is
due
to
the
movement
of
ions
in
a
the
liquids
liquid
or
in
electrolytic
solution
when
conduction
a
potential
there
is
often
difference
a
change
is
in
applied.
the
In
molten
ionic
compound
or
aqueous
solution
of
ions.
For
example,
molten
zinc
DID
chloride
decomposes
to
zinc
and
The
ZnCl
(l)
→
Zn(s)
+
Cl
2
resistance
inversely
its
is
is
a
molten
ionic
compound
or
a
solution
conducts
often
electrolytes
Strong
electrolytes
molten
have
Examples
ionic
The
ohms.
measured
1
÷
of
a
high
strong
concentration
electrolytes
unit
of
Conductivity
as
reciprocal
ohms
of
ions
in
DID
the
YOU
compounds,
e.g.
molten
KNOW?
are:
Ceramics

is
to
electricity.
Strong
electrolyte.
substance
containing
ohms:
that
a
proportional
conductivity.
resistance
electrolyte
of
(g)
Electrolytes
ions
KNOW?
2
is
An
YOU
chlorine:
lead
bromide,
PbBr
They
(l)
are
are
excellent
used
in
insulators.
high-voltage
2

aqueous
chloride,
solutions
of
NaCl(aq),
ionic
compounds
copper
sulfate,
(soluble
CuSO
salts),
e.g.
electricity
pylons
electricity
cables
to
keep
the
sodium
from
touching
(aq)
4
the

strong
acids
(acids
that
are
completely
ionised
in
aqueous
pylons.
from
e.g.
sulfuric
acid,
H
SO
2

strong
alkalis
solution),
Weak
weak
e.g.
acids
(acids
ethanoic
that
of
a
completely
acid,
HCl(aq)
are
CH
low
in
aqueous
concentration
electrolytes
only
ionised
partially
COOH(aq),
of
ions
in
the
EXAM
are:
ionised
methanoic
in
aqueous
acid,
solution),

It
HCOOH(aq)
weak
alkalis
solution),
(alkalis
e.g.
that
aqueous
are
only
partially
ammonia,
NH
ionised
in
is
meter
such
alternating
solution.
reading
of
as
electrolyte
that
shown
current
The
on
an
must
greater
the
in
be
the
can
Figure
used
tested
9.1.2.
to
strength
conductivity
be
A
prevent
of
the
the
using
a
power
conductivity
source
meta
llic
electrolysis
electrolyte,
of
the
be
the
higher
is
term
s
which
using
sway
ed
ions
POINTS
in
Conductors
have
a
low
resistance
to
the
passage
of
insulators
have
a
high
resistance
to
the
parti
cles
Do
no t
the
cond
uctio
n
movin
g
and
meta
llic
invo lv
es
electricity
movin
g
whereas
and
electr
olytic
.
cond
uctio
n
1
you
cond
uctio
n
the
by
Electro
lytic
invo lv
es
KEY
of
move.
‘electro
’
the
meter.
that
distin
ction
electr
olytic
in
strength
impo
rtant
be tween
aqueous
(aq).
3
The
TIPS
mak
e
3

made
NaOH(aq).
relatively
weak
that
acid,
are
hydroxide,
have
Examples
hydrochloric
are
clay.
4
sodium
electrolytes
electrolyte.

(alkalis
e.g.
(aq),
Ceramics
solution),
passage
electr
ons
.
of

It
is
impo
rtant
electricity.
to
2
The
conductivity
3
Electrolytic
4
An
in
metals
conduction
is
is
due
due
to
to
the
the
movement
movement
of
of
electrons.
the
ions.
is
a
molten
ionic
compound
or
a
solution
that
electro
ns
do
electrolyte
realis
e
ions
no t
in
in
that
conducts
move
electricity.
their
5
Strong
weak
electrolytes
electrolytes
have
have
a
a
high
low
concentration
concentration
of
of
ions
ions
and
in
me ta
ls
and
electro
lytes
in
a
of
parti
cular
ions
the
the
own.
differe
nce
applied
to
direc
tion
A
on
po ten
tial
has
ge t
to
be
them
to
electrolyte.
move
6
Molten
strong
7
Weak
ionic
acids
acids
compounds,
and
and
alkalis
alkalis
aqueous
are
are
strong
weak
solutions
of
salts
and
in
a
parti
cular
direc
tion.
electrolytes.
electrolytes.
81
9.2
Electrolysis
T
erms
LEARNING
used
Electrolysis
At
the
end
of
this
topic
be
able
define
electrolysis,
cathode,
cation
and
identify
ions
be
one
different
anode,
the
decomposition
place
in
an
of
a
compound
electrolysis
cell,
by
which
an
electric
can
be
a
current.
beaker
or
of
the
parts
of
electrodes.
an
The
electrolysis
beaker
cell
are
contains
shown
in
the
electrolyte.
Figure
The
9.2.1.
anion


is
takes
to:
can

electrolysis
you
Electrolysis
should
in
OUTCOMES
present
The
electrodes
are
rods
that
conduct
electric
current
to
and
from
in
the
electrolyte.
They
are
made
from
either
graphite
or
a
metal.
electrolytes

predict
an

ion
the
will
identify
electrode
to

The
anode
is

The
cathode
positive
electrode.
is
the
negative
electrode.
drift
oxidation
reactions
at
Identifying
the
the
which
the
ions
in
electrolytes
electrodes.
In
solid
only
each
salts,
occur
the
when
other
and
particles
the
are
salt
free
are
is
to
already
molten
present
so
that
as
the
ions.
ions
Electrolysis
separate
can
from
move:
+
NaCl(s)
d.c.
+
power
→
Na
→
Pb
(l)
+
Cl
(l)
–
2+
PbBr
supply
(s)
(l)
+
2Br
(l)
2
When
salts
dissolve
in
water
,
they
separate
into
their
ions.
For
example:
e
e
Anode
Cathode
+
KCI(s)
→
K
(aq)
→
Cu
+
Cl
(aq)
(negative
electrode)
2+
CuSO
(s)
2−
(aq)
+
SO
4
In
water,
acids
(aq)
4
form
hydrogen
ions
and
negative
ions:
Electrodes
+
HCl(g)
Electrolyte
In
water,
alkalis
form
→
H
hydroxide
(aq)
+
Cl
(aq)
ions:
+
NaOH(s)
Figure
9.2.1
An
electrolysis
direction
of
electrons
in
cell.
travel
→
Na
(aq)
+
OH
of
the
+
the
(aq)
The

Positive
ions

Negative
are
called
cations.
So
H
2+
,
2+
Pb
and
Cu
are
cations.
external
2−
circuit
is
shown
by
e
ions
are
called
anions.
So
Cl
,
SO
and
OH
ions
are
4
anions.
Electrode
DID
YOU
Which
Pure
low
and
water
also
contains
concentration
hydroxide
amounts.
reactions
KNOW?
of
ions
This
is
a
hydrogen
in
equal
because
We
can
do
predict
electrolysis.
the
ions
drift?
the
Unlike
direction
charges
in
which
attract
cations
and
like
and
anions
charges
repel.
drift
So:
water

undergoes
way
very
positively
charged
electrode
(cathode)
ions
(cations)
move
towards
the
negative
self-ionisation:
during
electrolysis
+
H
O(l)
2
H
(aq)
+
OH
(aq)

negatively
electrode
82
charged
(anode)
ions
(anions)
during
move
electrolysis.
towards
the
positive
during
Oxidation–reduction
When
the
occur.
The
The
in
ions
ions
nature
the
(see
reach
of
gain
the
9.3)
which
and
ion
is
its
the
or
ion
electrolyte.
reactions
electrodes,
lose
position
For
electrodes
oxidation–reduction
We
say
depends
of
concentration
discharged.
the
electrons.
discharged
The
at
the
play
ion
an
example,
on
in
they
the
the
an
types
part
aqueous
TIP
discharged.
of
ion
in
In so
me bo
oks yo
u may
present
electrochemical
important
in
are
EXAM
reactions
see ha
lf equ
ation
s show
ing
series
the ele
ctron
s rem
oved
or
determining
solution
gain
ed lik
e this
:
of
+
sodium
chloride,
sodium
chloride
the
ions
present
are
Na
(aq)
and
Cl
(aq)
from
the
2+
Zn
(aq)
+
and
H
(aq)
and
OH
(aq)
from
the
ionisation
of
water.
→
Some
examples
of
oxidation–reduction
reactions
at
the
electrodes
Zn(
s)
−
−
2e
are:
−
2Br
At
the
cathode
(see
Figure
(aq)
−
−
2e
9.2.2(a)):
→
Br
(l)
2

Cations
gain
electrons
from
the
cathode:
2+
Zn
(aq)
+
2e
+
2H
→
Zn(s)
→
H
−
(aq)
+
2e
(g)
2

Gain
of
electrons
is
reduction.
Reduction
always
happens
at
the
cathode.
EXAM

If
metals
the
are
cathode
electrolysis
At

the
or
form
cell.
anode
Anions
formed,
a
Gases
(see
lose
they
(aq)
2Br
usually
separate
formed
Figure
electrons
are
layer
deposited
at
bubble
the
off
top
from
either
or
as
a
bottom
the
layer
of
the
the
→
Rem
embe
r
cathode.
move
to
anion
s
9.2.2(b)):
to
TIP
on
that
the
catio
ns
cathod
e
move
to
the
and
anod
e.
anode:
Br
(l)
+
2e
2
−
4OH
(aq)
→
O
(g)
+
2H
2

Loss
of

Gases
electrons
is
oxidation.
O(l)
+
4e
2
Oxidation
always
happens
at
the
anode.
KEY
are
formed
bubble
immiscible
with
off
the
at
the
anode.
electrolyte
or
Liquids
dissolve
form
in
the
a
layer
if
POINTS
they
electrolyte.
1
Electrolysis
is
the
decomposition
a
of
a
b
Cathode
(–)
Anode
compound
(+)
e
by
2+
Zn
an
into
electric
its
elements
current.
Br
e
e
2
Br
Br
Electrodes
conduct
and
3
Zn
from
The
the
anode
electrode
9.2.2
a
Positive
electrons
ions
at
gain
the
electrons
at
the
cathode.
b
Negative
ions
the
such
lose
as:
to
is
electrolyte.
the
and
negative
Cations
anions
2+
Zn
that
current
positive
the
cathode
is
electrode.
anode.
4
Equations
rods
Br
e
Figure
are
electric
are
are
positive
negative
ions
and
ions.
−
(aq)
+
2e
→
Zn(s)
5
Water
self-ionises
to
form
+
−
and
2Br
very
−
(aq)
→
Br
(l)
+
small
amounts
of
H
2e
2
and
are
called
half
equations.
They
show
the
oxidation
and
6
parts
of
the
reaction
can
put
two
half
equations
together
to
form
the
overall
Oxidation
the
electrolysis
of
zinc
bromide
the
full
equation
will
(l)
2
occur
at
Reduction
→
Zn(s)
+
Br
reactions
occur
at
be:
the
ZnBr
reactions
anode.
equation.
7
For
ions.
separately.
the
We
OH
reduction
cathode.
(l)
2
83
9.3
The
electrochemical
series
and
electrode
products
The
LEARNING
We
At
the
end
electrochemical
of
this
topic
can
place
be
able
predict
chemical
making
use
of
the
of
how
electrolyte,
and
position
products
of
in
salts.
order
The
of
order
reactivity
of
by
reactivity,
reacting
with
the
metals
most
with
reactive
from
the
electrochemical
included
acids
in
(see
this
series
series
to
‘Displacement
(Figure
show
of
which
hydrogen’
9.3.1).
metals
displace
below).
we
go
up
the
electrochemical
series
the
metals:
concentration
type
of
called
also
series
the
of
ions
electrochemical
is
is
hydrogen
As
describe
top
Hydrogen
reactions
the
electrochemical

metal
to:
at

metals
you
different
should
series
OUTCOMES

increase

lose

become
in
reactivity
electrode
in
series
the
affect
the
electrons
more
stronger
readily,
reducing
so
form
positive
ions
more
readily
agents.
electrolysis.
Explaining
Metal
A
Cation
ylidaer
K
Na
Al
the
electrochemical
solution
of
its
ions.
series
We
can
can
displace
use
the
a
metal
electrochemical
series
to
predict
whether
or
not
a
reaction
is
likely
to
happen.
2
+
2
+
Example
Na
1
2
+
Mg
Will
magnesium
react
with
aqueous
copper( II)
sulfate?
3+
Al

Magnesium

So
is
higher
than
copper
in
the
electrochemical
series.
2
+
Zn
motA
Fe
in
a
Ca
sesol
Zn
from
+
snortcele
Mg
higher
it
reactions
K
erom
Ca
metal
below
displacement
magnesium
loses
electrons
and
forms
ions
more
readily
than
2
+
Fe
copper.
Magnesium

Copper
ions

So
is
a
better
reducing
agent.
2
+
Pb
Pb
H
H
are
better
at
accepting
electrons
than
magnesium
ions.
+
2
the
reaction
taking
place
should
be
one
in
which
magnesium
2
+
Cu
Cu
Ag
Ag
Au
Au
atoms
lose
electrons
and
copper
ions
gain
electrons.
+
When
excess
magnesium
ribbon
is
added
to
a
solution
of
copper( II)
+
Figure
9.3.1
The
electrochemical
sulfate,
the
deposit
of
blue
colour
copper
is
of
the
copper
sulfate
disappears
+
CuSO
(aq)
→
MgSO
4
Ionic
fo r
can
also
of
the
equation:
look
how
at
serie
s
easy
catio
ns
the
to
it
in
Example
2
Will
react
silver
electro
ns.

Silver
the
T
he

Zinc
lower
(aq)
→
Mg
(aq)
+
Cu(s)
is
the
in
catio
n
easier
to
and
is
lower
with
aqueous
than
zinc
in
zinc
the
chloride?
electrochemical
series.
loses
better
electrons
and
forms
ions
more
readily
than
silver.
Zinc
is
agent.
So
no
reaction
takes
place.
Zinc
ions
cannot
accept
electrons
from
the
it
is
accept
fo rm
reducing
the

catio
n
electro
n
because
silver
is
less
good
at
releasing
electrons
than
zinc.
fo r
an
Displacement
of
hydrogen
atom
s.
Only
acids
84
Cu
Cu(s)
accept
silver
serie
s,
+
+
is
the
me ta
l
Mg(s)
(aq)
4
2+
TIP
electro
chem
ical
term
s
pink
series
2+
We
a
seen.
Mg(s)
EXAM
and
metals
to
above
produce
hydrogen
hydrogen
in
gas.
the
electrochemical
This
is
because:
series
react
with

metals

they
above
hydrogen
are
more
reactive
than
hydrogen
a
lose
electrons
and
form
positive
ions
more
readily
b
than
+
ions
hydrogen
forms
H

hydrogen
ions
are
better

hydrogen
ions
are
converted
at
accepting
to
electrons
hydrogen
than
zinc
ions
gas:
+
(aq)
2H
+2e
→
H
(g)
2
Therefore
zinc
reacts,
for
example,
+
Zn(s)
+
2H
with
hydrochloric
acid:
2+
(aq)
→
Zn
(aq)
+
H
(g)
2
Figure
What
affects
the
electrode
9.3.2
a
There
copper
Solutions
often
contain
more
than
one
type
of
anion
or
cation.
aqueous
sodium
chloride
contains
the
ions
Na
b
For
+
example,
(aq)
On
and
OH
electrolysis,
(aq)
only
(see
(aq),
H
called
one
preferential
determining
The
type
of
cation
discharge
of
or
anion
ions.
is
There
discharged.
are
three
the
ion
YOU
can
the
electrochemical
in
the
electrochemical
series
are
discharged
series.
Ions
are
above
them.
discharged
discharge
at
series
So,
the
(see
in
preference
to
chloride,
if
Cu
+
and
cathode.
Figure
Cl
The
concentration
ions
concentrated
ion
concentrated
ion.
ions
when
a
We
ions
can
9.3.3).
are
Inert
take
But
or
inactive
in
So,
if
discharged
part
tends
So
are
also
in
present,
arrange
Cu
carbon
to
the
in
get
ions
sodium
in
are
electrodes.
in
to
solution
chloride
in
of
in
the
fits
aluminium
and
zinc.
below
carbon
reactivity
series
from
metal
OH
the
by
or
is
to
in
dilute,
the
less
to
the
not
the
extracted
usually
such
with
an
carbon.
it
OH
is
OH
is
electrolysis.
can
be
extract
For
by
from
building
around
a
the
more
metal
example,
extracted
boulders
cells
sometimes
to
by
copper
large
electrolysis
boulder
.
chlorine.
electrodes
electrodes,
be
ions.
chloride
formed,
platinum
Active
ore,
heating
convenient
preference
is
can
a
most
sodium
solution
oxygen
Graphite
reaction.
the
preference
discharged
Then
in
It
aqueous
preference
anions,
discharged
preference.
chemical
For
aqueous
series.
ions
anions
concentrated
discharged
solution.
Cl
the
silver
copper.
do
as
not
copper
2
aqueous
copper
sulfate,
do
take
part
in
SO
the
4
snoI
into
reaction.
NO
KEY
POINTS
1
The
electrochemical
metals,
with
the
series
most
shows
reactive
at
the
order
the
top.
of
reactivity
of
Cl
Br
2
A
metal
metal
3
The
the
higher
below
higher
metal
it
the
to
in
the
from
a
metal
lose
electrochemical
solution
in
the
electrons
of
its
can
displace
a
ions.
reactivity
and
series
form
series,
the
easier
it
is
for
ions.
Figure
4
If
more
than
solution
Preferential
the
and
type
undergoing
discharged
5
one
of
discharge
whether
or
not
or
electrolysis,
(preferential
electrochemical
anion
cation
only
is
one
present
of
the
in
ions
9.3.3
Discharge
series
for
anions
a
is
discharge).
depends
series,
the
erom
OH
3
esol
dipping
snortcele
electrodes
ylidaer

is
the
concentrated
electrolysed.
ion
of
the
2+
H
However
,

on
the
oxide,
sodium
silver
lower
Metals
2+
ones
of
KNOW?
include
between
in
with
crystals
This
We
of
reacts
and
factors
this:
position
of
chloride.
9.2).
electrochemical

reaction
zinc
(aq),
DID
is
no
with
Copper
nitrate
+
form
Cl
is
products?
the
on
the
position
concentration
electrode
is
inactive
of
of
or
the
the
ion
in
solution
active.
85
9.4
Examples
LEARNING
At
the
end
should

be
fused
of
this
able
describe
Electrolysis
OUTCOMES
the
halide
topic
electrolysis
as

At
the
cathode,

At
the
anode,
fused
metal
of
When
a
molten
reactions
lead( II)
halide
describe
dilute

the
electrolysis
the

the
copper(II)
inert
forming
a
metal.
lead
ions
lose
bromide
is
electrons
and
electrolysed
form
(Figure
a
halogen.
9.4.1),
the
electrode
At
the
cathode:
At
the
anode:
Pb
(l)
+
2e
→
Pb(l)
→
Br
of
2Br
(l)
and
(g)
+
2e
2
When
of
molten
sodium
chloride
dilute
is
electrolysed,
the
electrode
reactions
are:
+
At
the
cathode:
At
the
anode:
Na
(l)
+
e
→
Na(l)
→
Cl
chloride
describe
of
electrons
acid
electrolysis
concentrated
sodium
gain
2+
sulfuric
describe
ions
halides
are:
bromide

metal
electrolysis
you
to:
such
of
of
2Cl
(l)
sulfate
electrodes
using
and
(g)
+
2e
2
electrolysis
In
copper
both
used
these
cases
inert
electrodes
are
used
and
the
electrolyte
is
up.
electrodes.
Electrolysis
+
of
dilute
sulfuric
acid
−
Dilute
sulfuric
acid,
H
SO
2
electrodes
(Figure
+
H
(aq),
is
electrolysed
using
inert
platinum
4
9.4.2).
The
ions
present
in
dilute
sulfuric
acid
are
2−
(aq),
SO
(aq)
and
OH
(aq).
4
Bromine
+

gas
At
the
cathode,
H
ions
gain
electrons,
forming
hydrogen:
+
2H
(aq)
+
2e
→
H
(g)
2
Molten
lead

At
the
anode,
discharged.
OH
This
ions
is
(from
because
the
OH
2−
series
than
SO
water)
ions
are
are
preferentially
lower
in
the
discharge
−
ions.
The
OH
ions
lose
electrons
and
form
oxygen
4
and
water:
−
4OH
(aq)
→
O
(g)
+
2H
2
Molten
O(l)
+
4e
2
lead
+
During
bromide
the
electrolysis,
as
the
−
H
and
OH
ions
are
removed,
more
Heat
Figure
9.4.1
Electrolysis
of
molten
water
ionises.
water
in
The
acid
gets
more
concentrated
as
the
amount
of
lead
the
acidic
solution
decreases.
bromide
EXAM
T
he
electro
lysis
dilute
can
be
Electrolysis
of
When
sodium
the
is
a
(Figure
chloride
9.4.3),
the
adde
d
of
as
poor
electrolysed
at
the
of
chloride
inert
graphite
depends
on
the
ions.
concentrated
aqueous
to
impr
ove
of
pure
cond
ucto r
.
sodium
chloride
T
he
the
The
ions
present
are
Na
+
(aq),
H
(aq),
Cl
(aq)
and
OH
(aq).
+

At
the
cathode,
H
ions
are
preferentially
discharged.
This
is
+
water
because
they
are
lower
in
the
electrochemical
+
2H
(aq)
+
2e
→
H
(g)
2
86
using
anode
the
water
’.
cond
uctiv
ity
becaus
e
is
product
+
water
chloride
of
With
is
sodium
acid
thou
gh t
of
aqueous
electrodes
concentration
sulfu
ric
‘electro
lysis
acid
aqueous
TIP
series
than
Na
ions.

At
the
anode,
Cl
ions
are
preferentially
discharged.
This
is
because
Oxygen
gas
Hydrogen
Cl
ions
are
present
in
high
concentration.
The
concentration
effect
gas
has
more
influence
than
the
position
of
the
Cl
and
OH
ions
in
the
Dilute
discharge
series.
sulfuric
2Cl
(aq)
→
Cl
(g)
+
acid
2e
2
+
During
and
the
OH
electrolysis,
ions
in
the
solution
+
H
at
and
the
Cl
end
ions
of
get
the
used
up
electrolysis:
leaving
a
Na
solution
of
Pt
sodium
anode
hydroxide.
Pt
With
dilute
aqueous
sodium
cathode
chloride
Figure
9.4.2
Electrolysis
of
dilute
+

At
the
cathode,
H
ions
are
preferentially
discharged.
This
is
sulfuric
acid
+
because
they
are
lower
in
the
electrochemical
series
than
Na
ions.
Chlorine
+
2H
(aq)
+
2e
→
H
gas
Hydrogen
gas
(g)
2
Sodium

At
the
anode,
because
Cl
position
of
the
OH
ions
the
ions
are
ions
concentration
preferentially
present
in
of
4OH
are
the
the
(aq)
at
a
low
discharge
Cl
discharged.
concentration
series
This
and
has
more
O(l)
+
is
chloride
the
influence
that
ion.
→
O
(g)
+
2H
2
4e
2
+
During
and
the
Cl
more
electrolysis,
ions
in
the
solution.
H
+
and
Water
is
OH
ions
used
up
get
and
used
the
up,
leaving
solution
Na
becomes
concentrated.
Carbon
rod
Carbon
+
Electrolysis
of
aqueous
copper
sulfate
as
Figure
With
graphite
electrodes
(inert
anode
9.4.3
(+)
as
Electrolysis
2+
ions
present
are
Cu
+
(aq),
H
of
(–)
concentrated
electrodes)
aqueous
The
rod
cathode
sodium
chloride
2−
(aq),
SO
(aq)
and
OH
(aq).
4
KEY
POINTS
2+

At
the
cathode,
Cu
ions
are
preferentially
discharged.
This
is
+
because
they
are
lower
in
the
electrochemical
series
than
H
ions.
1
Electrolysis
of
fused
halides
2+
Cu
(aq)
+
2e
→
Cu(s)
produces
cathode

At
the
anode,
OH
ions
(from
the
water)
are
This
is
because
OH
2−
series
than
SO
ions
are
metal
and
a
at
the
halogen
at
preferentially
the
discharged.
a
lower
in
the
anode.
discharge
−
ions.
The
OH
ions
lose
electrons
and
form
oxygen
2
Electrolysis
of
dilute
sulfuric
4
and
water.
acid
4OH
(aq)
→
O
(g)
+
2H
2
ions
left
in
solution
are
H
+
the
cathode
the
anode.
hydrogen
and
oxygen
at
at
4e
2
+
The
O(l)
produces
2−
and
SO
The
solution
becomes
4
3
acidic
and
the
concentration
of
copper
sulfate
in
solution
Electrolysis
sodium
With
copper
electrodes
(active
At
the
cathode,

At
the
anode,
the
reaction
is
the
same
as
with
inert
active
electrode.
gets
Electrons
oxidised
are
because
removed
the
from
electrode
the
copper
is
to
an
ions
which
go
into
solution:
Cu(s)
→
Cu
copper
anode
gets
copper
cathode
thinner
sulfate
in
gets
as
thicker
copper
solution
is
as
copper
removed.
remains
the
is
4
(aq)
deposited.
The
same.
cathode.
is
The
chlorine
concentrated
oxygen
+
The
concentration
with
dilute
NaCl
or
NaCl.
Electrolysis
of
aqueous
copper
2e
sulfate
The
the
form
2+
copper
at
product
produces
electrodes.
with
copper
aqueous
chloride
hydrogen
electrodes)
anode

of
decreases.
copper
of
produces
cathode.
is
The
oxygen
are
used
if
or
electrodes
copper
anode
inert
the
product
electrodes
copper
are
at
if
active
used.
87
9.5
Electrolysis
Charge
LEARNING
the
end
of
this
topic
be
able

define

calculate
the
volumes

use
the
Faraday
of
mass
of
reactive
a
substance
anode)
produced
during
at
electrolysis
the
is
electrodes
proportional
(or
consumed
at
to:
to:
the
liberated
electrolysis
you
a
should
in
OUTCOMES
The
At
transfer
calculations
masses
the
electric

the
time
current
(in
amperes)
The
Q
=
electric
given
electrolysis
relationship
(in
seconds)
over
which
a
constant
current
passes.
and
substances
during

constant
charge
in
coulombs
Q
It
=
The
transferred
I
charge
Faraday
carried
by
C)
(amperes,
constant,
Faraday
constant
one
mole
×
in
electrolysis
is
t
current
(coulombs,
The
(C),
by:
of
time
A)
(seconds,
s)
F
(symbol
electrons
F)
is
or
the
one
quantity
mole
of
of
electric
singly
charge
charged
ions.
−1
Its

approximate
When
silver
we
is
value
is
electrolyse
deposited
at
96 500 coulombs
silver
the
nitrate
per
solution
mole
using
(C mol
silver
).
electrodes,
cathode.
+
Ag
One
the
DID
The
YOU
Faraday
after
constant
Michael
1867).
great
is
Faraday
Faraday
was
experimental
named

one
of
day
and
was
famous
for
His
laws
of
we
Cu
→
(96 500 C)
a
of
silver
is
Ag(s)
required
electricity
to
that
is
deposit
1 mol
required
to
of
silver.
remove
This
1 mol
anode.
electrolyse
copper
is
copper
sulfate
deposited
at
solution
the
using
copper
cathode.
(aq)
+
2e
→
Cu(s)
this
case,
it
requires
2
Faradays
(2
×
96 500 C)
to
deposit
1 mol
his
copper.
This
is
because
2
mol
of
electrons
are
needed
to
produce
electrolysis
1 mol
of
copper
atoms
from
1 mol
of
copper( II)
ions.
are:
1st
law:
The
mass
of
any
Electrolysis
product
is
liberated
proportional
electricity
in
to
which
calculations
electrolysis
the
has
quantity
of
Mass
of
substance
deposited
during
electrolysis
passed.
Example
2nd
law:
When
the
same
Calculate
quantity
of
through
a
electricity
is
the
of
mass
of
lead
deposited
at
the
cathode
during
passed
electrolysis
number
when
a
current
of
2.5 A
flows
through
molten
lead
electrolytes
−1
bromide
for
10
minutes.
(A
=
207,
F
=
96 500 C mol
)
r
in
series,
liberated
their
the
are
masses
in
equivalent
equivalent
the
of
products
ratio
weights.
weights
of
(Here
means
1
From
divided
charges
88
on
the
by
the
ions.)
the
electrons
molar
half
equation,
needed
to
deduce
deposit
the
1 mol
number
of
of
moles
substance:
2+
Pb
masses
is
of
of
of
lectures.
e
2+
the
scientists
from
When
+
amount
electrodes,
(1791–
In
his
Faraday
same
silver
KNOW?
(aq)
(l)
+
2e
→
Pb(l)
numerical
So
2 mol
of
electrons
are
required
per
mole
of
lead.
of
2
Use
the
needed
Faraday
to
constant
deposit
1 mol
to
of
deduce
the
number
of
coulombs
lead:
EXAM
TIP
−1
=
2F
=
2
×
96 500
=
193 000 C mol
When
3
Calculate
the
charge
transferred
during
the
carry
ing
electro
lysis
So
remem
ber
Q
=
It
Q
=
2.5
×
10
×
60
=

1500 C
chan
ge
hour
s
4
Calculate
the
mass
by
simple
proportion,
using
the
mass:
dedu
ce
of
207 g
are
deposited
by
193 000 C.
calcu
latio
ns
to:
minut
es
into
relative

atomic
out
electrolysis:
the
num
ber
electro
ns
deposi
t
or
second
s
one
need
ed
mo le
of
to
the
produc
t.
1500
So
mass
deposited
by
1500 C
×
207
=
193 000
=
If
you
the
are
asked
calculation
Volume
of
to
is
gas
calculate
exactly
the
formed
the
1.6 g
mass
lead
of
metal
lost
from
the
anode,
same.
during
electrolysis
Example
A
dilute
using
a
solution
current
of
of
sulfuric
0.20 A.
acid
is
electrolysed
Calculate
the
for
volume
of
exactly
1 hour
oxygen
released
at
−1
the
1
anode
From
at
the
electrons
r.t.p.
half
(F
=
96 500 C mol
equation,
transferred
4OH
(aq)
to
deduce
the
produce
→
O
)
(g)
number
1 mol
+
2H
2
So
2
4 mol
Use
the
of
electrons
Faraday
are
to
of
moles
of
substance:
O(l)
+
4e
2
transferred
constant
of
deduce
per
the
mole
of
number
oxygen.
of
KEY
coulombs
1
transferred
to
produce
1 mol
of
POINTS
The
Faraday
quantity
=
4 F
=
4
×
constant
is
the
oxygen:
carried
96 500
or
of
by
1 mol
electric
1 mol
of
of
singly
charge
electrons
charged
−1
=
386 000 C mol
ions.
3
Calculate
the
charge
transferred
during
the
electrolysis:
2
Q
=
Electric
=
It
current
time
So
Q
=
0.20
×
=
720 C
1
×
60
×
charge
(in
(in
(in
coulombs)
amperes)
×
seconds).
60
3
The
value
of
the
Faraday
−1
constant
4
Calculate
the
volume
by
simple
proportion,
using
the
is
96 500 C
mol
relationship
4
The
masses
or
volumes
of
3
that
1 mol
of
gas
at
r.t.p.
occupies
24 dm
:
the
products
of
electrolysis
3
24 dm
of
gas
released
by
386 000 C.
can
be
found
number
720
So
volume
released
by
720 C
×
of
using
the
electrons
required
24
=
per
mole
the
value
of
product,
386 000
3
=
constant
0.0448 dm
charge
of
the
and
Faraday
the
quantity
of
passed.
3
=
45 cm
(to
2
significant
figures)
89
9.6
Applications
of
electrolysis
Extracting
LEARNING
Many
At
the
end
of
this
topic
be
able
describe
metallic
electrolysis
of
between
on
by
Metals
the
metal
in
series
purification
of
by
O
2
metals

Metals
using
describe
their
placed
in
oxides
the
with
carbon
electrochemical
and
zinc.
below
carbon
in
the
electrochemical
series
can
be
carbon.
For
example:
(s)
+
3C(s)
→
4Fe(l)
+
3CO
(g)
2
above
carbon
electrolysis.
and
in
The
the
electrochemical
oxides
sodium
of
metals
cannot
be
such
reduced
series
as
are
extracted
aluminium,
because
enough
reducing
agent.
It
cannot
release
carbon
electrons
is
as
not
well
anodising.
the
metals
higher
Purification
Anode:
Power
Cathode:
a
supply
a
of
thin
sheet
impure
(+)
copper
be
3
strong
as
bar
reducing
electroplating
a

by
can
the
electrolysis
describe
Carbon
aluminium
oxides
magnesium

extracted
the
2Fe
describe
be
extraction
based
electrochemical

can
temperatures.
reduced
position
electrolysis
to:

by
metals
high
series

using
you
at
should
metals
OUTCOMES
(–)
Many
metals

The
impure

A

The
of
can
in
the
series.
metals
be
purified
by
electrolysis.
of
pure
metal
is
the
anode.
copper
In
thin
sheet
of
electrolyte
the
pure
is
purification
a
metal
soluble
of
copper
is
the
salt
cathode.
of
the
(Figure
pure
metal.
9.6.1):
Anode
2+

sludge
the
copper
containing
at
the
anode
lose
electrons
and
form
Cu
ions
2+
sulfate
Cu(s)
impurities
→
Cu
(aq)
+
2e
solution

Cu
Figure
atoms
Copper
2+
9.6.1
the
anode
the
cell
becomes
the
copper
thinner
and
the
impurities
fall
to
the
bottom
of
(aq)
The
by
purification
of
copper

as
an
anode
ions
at
sludge
the
cathode
gain
electrons
and
form
Cu atoms
electrolysis
2+
Cu

the
on
(aq)
cathode
+
2e
→
becomes
Cu(s)
thicker
because
the
pure
metal
is
deposited
it.
Electroplating
+
Nickel
Silver
to
be
spoon
Electroplating
layer
anode
involves
coating
of
the
surface
of
one
metal
with
a
plated
of
another,
usually
less
reactive,
metal.
We
electroplate
articles
(cathode)
because
it:
+
Ag→ Ag

+ e
makes
nickel
them
more
resistant
to
corrosion,
e.g.
chromium
plating,
plating
+
Ag
+ e
→ Ag

improves
Figure
Silver
Figure
9.6.2
cyanide
Electroplating
with
90
solution
silver
a
spoon
their
9.6.2
appearance,
shows
the
e.g.
apparatus
plating
with
required
for
silver.
electroplating.
In
electroplating:

the
anode
is
the

the
cathode

the
electrolyte
is
pure
EXAM
metal
the
object
to
is
soluble
be
electroplated
(usually
a
metal)
Mak
e
a
salt
of
the
pure
metal
at
the
anode.
the
silver
plating,
Ag
ions
are
formed
at
the
anode
from
Ag
atoms.
+
The
Ag
atoms.
ions
accept
These
form
electrons
the
layer
from
(silver
the
cathode
plating)
on
and
the
become
silver
sure
the
know
purifi
catio
n,
natu
re
and
Anodising
you
be tween
electr
oplatin
g
anod
ising
cathode.
that
differe
nce
meta
l
+
In
TIP
in
of
cathod
e,
and
term
s
the
of
anod
e
and
the
electr
olyte.
Anodising
oxide
layer
reactivity
used
and
The
by
wear.
is
reaction
surface
of
a
such
of
The
as
metal.
nickel
apparatus
It
or
conditions
the
is
thickness
used
to
aluminium,
to
increase
used
for
of
an
reduce
so
that
corrosion
anodising
unreactive
the
they
can
be
resistance
aluminium
is
9.6.3.
the
metal.
present
with

The
cathode

The
electrolyte
the
increasing
variety
normally
During
of
the
Figure
anode
layer
process
metals,
a
reduce
in
the
on
of
under
shown

is
is
When
on
sodium
usually
is
the
anodising
surface
of
aluminium,
the
metal
is
the
thin
first
oxide
removed
hydroxide.
unreactive,
sulfuric
reaction,
the
e.g.
carbon.
Aluminium
Carbon
anode
cathode
acid.
sulfuric
acid
is
electrolysed
to
form
oxygen
Oxygen
and
hydrogen.
gas
Hydrogen

Oxygen
gas
is
produced
at
the
gas
anode:
Electrolyte
4OH
(aq)
→
O
(g)
+
2H
2
O(l)
+
4e
(dilute
2
sulfuric

The
oxygen
gas
reacts
with
the
anode
and
forms
a
thick
oxide
acid)
layer:
Figure
4Al(s)
+
3O
(g)
→
2Al
2
O
2
DID
The
KEY
9.6.3
Anodising
YOU
KNOW?
ability
of
carbon
oxides
depends
temperature.
Metals
below
carbon
in
the
electrochemical
series
can
extracted
from
their
oxides
by
reduction
with
Metals
above
extracted
carbon
using
in
the
electrochemical
series
are
can
be
purified
by
by
However
,
electrolysis
using
and
pure
metal
an
impure
Electroplating
layer
5
In
to
6
of
is
another
used
plated,
Anodising
surface
the
of
is
a
the
this
because
used
is
above
1450 ºC.
method
the
is
not
energy
this
cost
temperature
of
is
cathode.
to
coat
the
surface
of
one
metal
with
high.
a
the
pure
metal
is
the
anode
and
the
object
cathode.
to
metal.
electrolyte
be
the
metal.
electroplating,
be
is
if
metal
too
4
can
carbon
maintaining
anode
example,
oxide
temperature
electrolysis.
used
Metals
For
the
carbon.
reduced
3
reduce
on
be
magnesium
2
to
POINTS
metal
1
aluminium
(s)
3
increase
The
metal
sulfuric
the
to
thickness
be
of
anodised
oxide
is
the
layer
on
anode
the
and
acid.
91
10
Rates
of
10.1
reaction
Following
of
a
Rate
LEARNING
the
end
of
this
topic
be
reaction
reaction
of
reaction
able
is
the
with
time
at
a
−3
define
rate
stated
in
concentration
temperature.
The
of
a
units
reactant
of
rate
or
of
a
to:
reaction

change
you
product
should
course
OUTCOMES
Rate
At
of
the
of
are
mol dm
−1
s
change
reaction
in
concentration
of
–3
reactant

describe
out
of
how
to
experiments
reaction
−3
carry
on
rate
We
gas
measurement
of
mass
use
of
titrations
in
light
volume,
and
and
cannot
measure
experiments
on
proportional
intensity
or
to
The
and
of
rate
of

these
Effect
choosi
ng
appro
priate
term
s

If
and
of
whe th
er
can
be
size
to
of
or
of
the
off
in
no t
course
of
is
we
e.g.
of
changes
temperature
that
rate,
at
Effect
a
on
of
when
change
carrying
something
volume
of
out
that
gas,
(s)
is
colour
temperature,
solids.
have
to
So
concentration
when
make
sure
carrying
that
out
only
one
time.
keep
reactants
particle
temperature
size
solids
the
concentration
and
particle
on
rate:
and
particle
constant.
keep
the
temperature
constant.
on
rate:
keep
the
concentration
and
constant.
Measuring
the
volume
of
gas
given
off
states
they
The
of
is
volume
or
of
gas
given
upturned
magnesium
with
off
is
measured
measuring
cylinder
hydrochloric
acid
at
time
initially
can
be
intervals
full
of
using
water
.
followed
in
a
The
this
gas
reaction
way.
react
ion
+
2HCl(aq)
→
MgCl
(aq)
+
H
2
fo llo
w
the
(g)
2
the
react
ion
measu
remen
t
a
b
syringe
of
Measuring
vo lum
e
mass.
no t
loss
Gas
collected
Delivery
in
cylinder
tube
T
his
hydr
ogen
is
becaus
e
has
such
Rubber
bung
a
Magnesium
dens
ity.
Magnesium
Water
ribbon
ribbon
Hydrochloric
acid
H
Figure
10.1.1
Measuring
acid
92
this
reaction
are
we
rate:
are
concentration
solid
of
that
Gas
usin
g
low
so
measure
mass,
a
with
reactants
varied
reactants
of
of
syringe
gas
a

of
Effect
size
titra
ted.
shou
ld
course
gas
directly,
for
conductivity.
determine
factors
Mg(s)
you
reaction
taken
produc
ts
their
hydr
ogen
given
rate
cons
ider
react
ants

an
me th
od
measu
ring
react
ion,
or
)
=
TIPS
When
in
the
reaction
particle
size
fo r
)
concentration,
electrical
experiments

of
(mol dm
−1
s
concentration
rates
product
transmission.
Following
EXAM
(mol dm
time
involving
of
changes
reaction
rate
measurement
the
of
or
a
the
using
a
rate
gas
of
the
reaction
syringe,
b
using
drochloric
of
a
acid
magnesium
measuring
with
hydrochloric
cylinder
Measuring
change
in
mass
Cotton
Marble
wool
chips
bung
If
a
gas
is
mixture
given
off
decreases.
in
a
The
reaction
mixture,
decrease
in
mass
the
is
mass
of
measured
the
at
reaction
measured
and
hydrochloric
acid
Conical
time
intervals,
CaCO
(s)
+
for
example,
2HCl(aq)
the
→
reaction
CaCl
3
+
Figure
CO
2
Measurement
Small
(aq)
in
samples
of
are
rate
by
(g)
flask
10.1.2.
+
H
2
O(l)
2
sampling
removed
from
the
reaction
mixture
at
time
Top-pan
intervals
and
analysed
by
titration.
The
reaction
of
potassium
iodide
balance
with
dilute
acidified
hydrogen
peroxide
can
be
followed
in
this
way.
Figure
2KI(aq)
+
2HCl(aq)
+
H
O
2
(aq)
→
2H
2
O(l)
+
I
2
(aq)
+
10.1.2
The
reaction
chips
2KCl(aq)
reactants
gets
a
are
deeper
and
of
iodine.
1
T
ake
2
Immediately
into
3
The
fixed
deeper
method
volumes
after
sodium
Titrate
colourless.
reaction
due
to
the
proceeds,
increased
the
solution
concentration
samples
each
at
sample
has
solution
with
particular
The
end
iodine
point
of
is
accompanied
decrease
in
the
contents
of
by
mass
the
a
of
the
flask.
to
been
stop
standard
times.
taken,
the
pipette
reaction
sodium
the
sample
continuing.
thiosulfate
Time
solution.
how
takes
4
marble
is:
of
sample
the
brown
carbonate
each
As
of
hydrochloric
2
acid
The
with
the
titration
is
when
the
brown
colour
of
the
for
long
disappear
viewed
disappears.
it
Sodium
the × to
thiosulfate
solution
when
and
dilute
hydrochloric
acid
from
above
5
Repeat
this
Measuring
When
of
S
2
The
the
sodium
sulfur
Na
process
is
O
2
time
each
taken
thiosulfate
sample.
for
reacts
a
solid
with
to
obscure
hydrochloric
a
acid,
cross
a
suspension
formed.
(aq)
+
2HCl(aq)
→
2NaCl(aq)
+
S(s)
+
SO
3
(g)
+
H
2
suspension
cross
with
placed
of
sulfur
below
the
gets
denser
reaction
and
flask
denser
(Figure
until
10.1.3).
it
O(l)
2
obscures
The
time
a
taken
Figure
10.1.3
The
reaction
thiosulfate
for
this
to
happen
is
recorded.
The
experiment
is
then
of
repeated
hydrochloric
varying
only
one
of
the
factors,
e.g.
changing
only
the
long
it
Rate
or
of
reaction
product
When
make
with
carrying
sure
is
the
time
out
that
change
at
a
in
stated
experiments
only
one
factor
concentration
of
a
The
progress
how
to
is
determine
varied
at
a
rate,
we
have
to
DID
YOU
‘disappear’
The
volume
of
of
progress
samples
some
gas
reactions
or
mass
can
be
changes
followed
with
by
measuring
in
of
some
reactions
at
various
times
titrating
the
can
be
time.
followed
thiosulfate
throughout
the
a
takes
of
for
the
a
above.
by
reacts
with
reaction
is
used
deduce
of
the
iodine
iodine
to
because
form
taking
and
products.
The
end
then
of
the
titration
can
be
samples.
suspension
progress
to
concentration
made
When
from
KNOW?
titrations
point
it
cross
when
time.
colourless
5
how
the
temperature.
it
4
for
reactant
Sodium
3
is
timing
takes
viewed
2
by
POINTS
to
1
acid
temperature.
followed
KEY
sodium
with
of
solid
reaction
cross
can
below
is
formed
be
the
in
followed
reaction
a
reaction,
by
timing
mixture
to
the
how
be
long
obscured.
clearer
if
starch
solution
colour
change
is
from
a
few
are
at
added.
the
blue-black
drops
to
end
of
The
point
colourless.
93
10.2
Determining
of
reaction
Graphs
LEARNING
the
end
showing
progress
of
reaction
OUTCOMES
Excess
At
rates
of
this
topic
magnesium
reacts
with
dilute
hydrochloric
acid
of
you
−3
concentration
should
be
able
0.4 mol dm
to:
Mg(s)
+
2HCl(aq)
→
MgCl
(aq)
+
H
2

use
of
data
to
various
deduce
factors
the
on
rate
The
of
interpret
concentration
hydrogen
reaction

gas
of
the
released
hydrochloric
rises.
Typical
acid
falls
results
are
as
the
given
volume
in
T
able
of
10.2.1.
graphical
T
able
representation
in
(g)
2
effect
studying
of
rates
data
of
10.2.1
obtained
reaction
Concentration
of
0.4
0.3
0.2
0.1
0.05
0.0
0.0
0
48
96
144
168
192
192
0
15
43
100
180
500
600
−3
acid

describe
how
changes
as
rate
of
(mol dm
)
reaction
3
a
reaction
proceeds
Volume
of
H
(cm
)
2

describe
of
the
graphs
against
against
against
of
general
shape
Time
(s)
concentration
time,

concentration
1/time
and
When
time,
rate
we
we
reaction
time.
(Figure

When
get
concentration
a
downward
proceeds.
So
the
of
reactant
curve.
The
reaction
is
(in
curve
this
case
gets
getting
less
slower
acid)
steep
as
it
against
as
the
proceeds
10.2.1(a)).
we
an
plot
get
plot
volume
upward
curve.
of
product
The
curve
(hydrogen)
gets
less
against
steep
as
the
time
we
reaction
a
3–
)
proceeds.
fo
Faster
How
does
cirolhcordyh
Although
Slower
again,
the
reaction
is
getting
slower
is
it
proceeds
time,
e.g.
When
Time
rate
rate
is
change
defined
in
as
terms
a
of
reaction
proceeds?
concentration,
we
can
plot
rate
something
that
changes
volume
excess
of
proportionally
gas,
calcium
mass,
colour
carbonate
to
or
reacts
concentration
electrical
with
against
conductivity.
hydrochloric
acid,
we
(s)
can
b
plot
(Figure
time
Slower
So,
10.2.1(b)).
rate
dica
noitartnecnoC
md lom(
(Figure
either
the
10.2.2(a))
(Figure
volume
or
the
of
carbon
change
in
dioxide
mass
of
released
the
against
reaction
time
mixture
against
10.2.2(b)).
rate
CaCO
(s)
+
2HCl(aq)
→
CaCl
2
3
(aq)
+
CO
2
(g)
+
H
2
O(l)
2
H
fo
emuloV
a
b
No
y
gives
the
rate
reaction
x
rate
2
erutxim
Faster
further
OC
10.2.1
The
reaction
between
where
less
and
in
as
a
a
can
steep
be
decrease
concentration
is
y
acid
Reaction
recorded
slower
of
Reaction
ssaM
hydrochloric
is
gradient
faster
fo
magnesium
Reaction
emuloV
Figure
(s)
gnitcaer
fo
Time
gradient
is
is
faster
where
steeper
Reaction
x
acid
Time
Time
with
time,
volume
of
b
an
H
gas
2
94
increase
with
in
time.
Figure
10.2.2
Curves
for
a
CO
increase
2
v.
time,
b
mass
decrease
v.
time
slower
In
both
graphs
we
can
see
that:
3
gradient
has
drawn
gradient
The
rate
to
the
(slope)
decreases
the
rate
at
particular
point
where
a
tangent
curve.
decreases
as
a
the
as
the
reaction
reaction
proceeds.
emuloV

The
gives
35 cm
40
3
gas
produced
30
fo

been
y/x
mc( sag
The
)

proceeds.
stops
10
After
Figure
10.2.3
shows
how
we
can
how
long

the

when
it
volume
the
of
gas
the
reaction,
has
at
to
a
produce
given
a
given
volume
of
gas
measure
precipitate
the
3
20
Figure
time
sulfur
40
taken
(see
60
80
Time ( s)
thiosulfate–acid
of
0
time
finished.
sodium
we
the
reaction
produced
30 cm
produced
for
the
10.1).
reaction
cross
We
10.2.3
can
to
be
see
how
l CH
by
a
gas
)qa(
this
obscured
for
reaction
Analysing
In
takes
37 s,
find:
of

at 60 s
20
rate
fo
using
with
concentration
different
of
concentrations
acid
of
by
acid
doing
at
several
constant
noitartnecnoC
changes
experiments
temperature.
1
A
graph
is
then
of
concentration
against
time
plotted
(see
Figure
taken
for
the
cross
to
be
obscured
10.2.4).
1
–1
( s
)
t
Rate
that
the
is
inversely
the
rate
of
proportional
reaction
concentration
So
(proportional
the
to
from
this
1/time)
graph,
is
we
can
proportional
see
to
Figure
10.2.4
acid.
KNOW?
1–
YOU
time.
)
DID
of
to
s
of
of
the
concentration
line.
line
or
line
curve
reactant
against
may
be
depends
is
in
rate
an
on
does
upward
the
not
always
curve.
reaction
The
and
produce
exact
a
shape
whether
or
not
a
etaR
particular
The
md lom(
plot
straight
3–
A
excess.
Time
Rate–time
Figure
When
we
curve.
At
reaction
plot
the
rate
of
reaction
beginning
proceeds
the
of
rate
the
against
time,
reaction,
gets
slower
the
and
the
rate
graph
is
slower
is
usually
highest
(Figure
but
10.2.5
a
as
the
10.2.5).
EXAM
KEY
In
POINTS
TIP
some
grap
hs
conc
entra
tion
1
As
a
reaction
proceeds
the
rate
of
reaction
Rate
of
reaction
particular
3
A
graph
points
of
can
on
mass
be
the
deduced
curve
change
of
against
by
a
drawing
tangents
concentration–time
a
gas
is
a
downward
time
for
a
reaction
be
time
at
graph.
pro po
rtion
al
early
react
ion.
calcu
late
that
of
produces
curve.
Rate
of
reaction
is
proportional
to
1/time.
on
Y
ou
the
react
ion
initi
al
4
the
appear
s
decreases.
to
2
(s)
graphs
in
to
the
can
easily
initi
al
by
the
rate
taking
grad
ient
of
the
the
grap
h.
5
A
plot
of
reaction
concentration
changes
with
against
increase
1/time
in
shows
how
the
rate
of
concentration.
95
10.3
How
and
concentration
surface
rates
The
LEARNING
effect
the
end
of
this
topic
be
able
a
describe
the
reaction
concentration
how
change
concentration
(keeping
of
reactants
everything
else
carbonate
with
excess
affects
the
increasing
rate
why
change
of
(s)
+
affects
the
the
reaction
rate
of
acid:
2HCl(aq)
→
CaCl
(aq)
+
CO
(g)
+
H
2
O(l)
2
the
concentration
(Figure
of
hydrochloric
10.3.1).
The
final
acid,
volume
increases
of
the
carbon
dioxide
is
the
same
in
each
experiment
because
the
hydrochloric
acid
rate
in
excess
how
(the
calcium
carbonate
is
the
limiting
reagent).
changing
Using
surface
area
changes
the
data
Increasing
reaction
explain
why
changing
changes
the
rate
deduce
how
concentration
affects
rate
the
concentration
increases
the
rate
of
of
reactants
a
(at
reaction.
constant
However,
temperature)
not
all
reactants
surface
behave
area
to
rate
generally

increases
the
reaction
describe
of
In
in
is

generally
2
reaction
released
concentration
of
reaction
rate
reaction
explain
of
constant).
hydrochloric
3

rate
in
CaCO
concentration
of
on
to:
calcium

reaction
you
of
should
of
affect
OUTCOMES
Increasing
At
of
area
in
this
way.
T
able
10.3.1
compares
the
rate
of
reaction
of
of
formation
of
iodine
from
iodide
ions
(I
)
and
hydrogen
peroxide
reaction
+
(H
O
2

use
data
to
deduce
the
)
in
various
factors
on
solution
(H
)
when
different
concentrations
of
2
effect
reactants
of
acid
rate
are
used.
of
reaction
T
able
10.3.1
Reaction
rates
of
iodide
ions
(I
)
and
hydrogen
peroxide
(H
O
2

explain
the
danger
of
explosive
divided
combustion
)
in
2
+
acid
of
solution
(H
)
finely
Experiment
Relative
Concentration
Concentration
Concentration
number
rate
of
of
of
substances.
+
of
H
O
2
I
−3
reaction
H
2
(mol dm
−3
)
(mol dm
−3
)
(mol dm
)
–3
2 mol dm
acid
(highest
concentration)
decudorp
A
1
0.1
0.1
0.1
B
2
0.2
0.1
0.1
C
2
0.1
0.2
0.1
D
1
0.1
0.1
0.2
–3
2
1 mol dm
acid
OC
fo
emuloV
–3
0.5 mol dm
(lowest
acid
You
concentration)

Time
can
see
doubling
that:
the
concentration
of
H
O
2
and

doubling
and
,
doubles
the
rate
(comparing
A
2
B)
the
concentration
of
I
doubles
the
rate
(comparing
A
C)
etaR
+

doubling
the
Explaining

Concentration
of
Increasing
concentration
the
the
effect
of
of
H
has
no
effect
concentration
concentration,
decreases
on
the
(comparing
rate
of
distance
A
and
D).
reaction
between
the
acid
3
particles.
Figure
10.3.1
Increasing
of
acid
rate
of
the
increases
reaction
calcium
96
are
more
particles
per
dm

So
there
are

So
there
is
more
collisions
per
second
between
the
particles.
the
between
carbonate
hydrochloric
There
concentration
acid.
and
a
greater
chance
of
the
particles
reacting
(Figure
10.3.2).
Water
molecules
not
shown
EXAM
TIP
Rem
embe
r
,
same
Calcium
mass
chips
is
that
of
if
the
marbl
e
taken,
the
carbonate
combi
ned
particles
of
all
large
+
3
+
ions) per dm
The
The frequency of collisions is high.
effect
When
the
and reacting.
of
marble
reaction
surface
chips
rate
the
depends
effect
of
area
(calcium
concentration
on
rate
carbonate)
on
of
the
surfac
e
The frequency of collisions is low.
of
is
less
from
than
combi
ned
More chance of particles colliding
and reacting.
Explanation
chips
3
that
10.3.2
area
ions) per dm
Many acid particles (H
Less chance of particles colliding
Figure
surfac
e
parti
cles
High concentration of acid
Low concentration of acid
Few acid particles (H
the
the
react
particle
size
on
of
of
of
all
the
chips.
reaction
reaction
with
of
rate
smal
l
area
hydrochloric
the
marble
acid,
chips
2 cm
2 cm
(everything
of
the
acid
else
marble,
to
react.
being
the
kept
greater
Breaking
the
is
up
same).
the
the
The
number
marble
greater
of
into
the
particles
smaller
surface
exposed
pieces
area
to
the
exposes
2 cm
more
(see
surfaces,
Figure
react
resulting
10.3.3).
faster
than
So,
in
more
with
larger
particles
the
same
being
mass
of
available
marble,
to
react
smaller
pieces
Large
pieces.
piece
of
marble
2
Sur face
The
explanation
size
of
more
solid
the
particles
particles
collisions
for
per
is
increasing
similar
available
second
to
and
to
react
rate
that
with
therefore
of
for
the
the
reaction
with
rate
of
So
there
reaction
There
are
is
are
CUT
more
faster.
More
Combustible
Some
can
The
processes
sawdust
particles
fine
of
from
metal
powders
cause
sawmills,
from
are
fine
powders
particles
metal-working
extremely
of
or
to
flour
coal
combustible
get
into
from
dust
(burn
the
flour
from
coal
readily
air
.
have
a
in
tiny
mining.
very
large
surface
area
compared
with
their
air)
volume.
because
A
smaller
or
spark
from
a
machine
can
cause
them
to
2
1
Increasing
the
concentration
of
a
reagent
generally
10.3.3
Cutting
up
marble
increases
DID
rate
of
Rate
increases
as
the
concentration
of
reactant
increases
frequency
of
collisions
of
the
reacting
particles
first
verifi able
the
surface
area
of
a
solid
increases
explosion
in
flour
mill
happened
on
14
increases.
December
Increasing
KNOW?
because
a
the
YOU
reaction.
The
3
48 cm
POINTS
the
2
area
explode.
Figure
KEY
pieces
lit
Sur face
match
exposed
These
mills,
Eight
they
sur face
powders
industrial
be
24 cm
decreasing
concentration.
acid.
area
the
rate
1785
in
Torino,
Italy.
of
reaction.
4
For
the
surface
5
Finely
have
same
area
divided
a
large
total
than
mass,
larger
substances
surface
smaller
particles
have
a
larger
particles.
area
may
for
explode
their
in
the
air
because
they
volume.
97
10.4
How
temperature
catalysts
of
The
LEARNING
the
end
reaction
effect
of
this
topic
be
able
describe
affects
10.4.1
how
the
explain
in
shows
between
rate
of
time
using
temperature
simple
taken
the
on
reaction
rate
how
changing
sodium
the
thiosulfate
temperature
and
changes
hydrochloric
acid
the
(see
rate
of
10.1).
to
same
obscure
a
cross
concentration
of
at
different
thiosulfate
temperatures
and
acid
each
was
recorded
time.
reaction
T
able

temperature
to:
The

of
you
reaction
should
rates
OUTCOMES
T
able
At
affect
and
terms
10.4.1
how
−1
temperature
of


the
rate
reaction
describe
how
the
rate
use
data
of
affects
of
Time
(ºC)
cross
affect
to
obscure
1/time
(s
)
(s)
20
47
0.021
30
23
0.043
40
12
0.083
50
6
0.167
reaction
to
factors
catalysts
T
emperature
deduce
on
rate
the
of
effect
reaction.
As
the
temperature
1–
)
obscured
increases,
decreases.
The
the
third
time
column
taken
for
(1/time)
the
is
cross
to
be
proportional
to
the
s
3–
rate
of
reaction.
md lom(
increases.
by
The
So
rate
as
the
temperature
approximately
increases,
doubles
as
the
the
rate
of
reaction
temperature
rises
10 ºC.
noitcaer
Explaining
the
effect
of
temperature
on
rate
of
reaction
fo
etaR
In
Temperature
Figure
10.4.1
The
on
effect
the
rate
to
react
of
energy.
temperature
(°C)
of
order
amount
So
the
be
explained
of
reaction

TIP
tions
abou
t
rates
The
higher
it
is
you
or
of
fastER
use
proportion
The
effect
must
activation
of
of
the
have
a
energy.
particles
temperature
minimum
At
have
on
a
low
this
energy.
reaction
rate
following
can
way:
The
temperature
The
higher
particles
temperature,
reactant
the
increases
move
the
the
faster
more
average
and
more
energetic
kinetic
energy
of
energetically.
are
the
collisions
particles.
temperature,
having
The
the
greater
or
equal
is
to
the
the
proportion
activation
of
reactant
energy.
number
of
So
collisions
the
rate
per
unit
time
leading
to
a
reaction
is
increases.
the
instea
d
is
effect
of
catalysts
on
rate
of
reaction
ge ts
high
ER
react
ion
above
e.g.
The
react
ion
the
energy
compa
rativ
e
fast
A
catalyst
getting
is
a
used
substance
that
speeds
up
a
chemical
reaction
without
up.
of
at

tempe
ratures
’.
The
the

catalyst
end
Only
a
as
is
at
tiny
reaction
98
particles
impo
rtant
phrase
s,
tempe
rature’
high
the
the
the
increased.
‘the
slow.
the
of

‘rate
small
collide,
called
answ
ering
react
ion
wo rd
s
is
the
particles.
particles
that
in
Increasing
between

ques
a
is
reaction
the
When
only
they
This
temperature

EXAM
when
by
not
the
used
start
amount
a
vast
of
up
of
in
the
the
catalyst
amount.
reaction.
Its
mass
is
the
same
reaction.
is
needed
to
increase
the
rate
of
at

The
is
chemical
the
same
composition
as
that
at
the
of
the
catalyst
at
the
end
of
the
reaction
beginning.
80
Catalysts
can
70
be:
3
e.g.
manganese( IV)
oxide
or
copper( II)
oxide
can
be
used
to
mc(
solids,
)

Manganese (IV) oxide
60
2
Lead (IV) oxide
O
up
the
decomposition
of
hydrogen
peroxide
catalysts
speed
Figure
that
up
work
many
10.4.2
in
solution,
reactions
shows
the
in
e.g.
hydrogen
ions
(H
)
are
used
to
solution.
effect
of
various
catalysts
on
40
emuloV
+

50
fo
speed
30
Co
20
pp
of
hydrogen
peroxide.
In
the
absence
of
a
peroxide
decomposes
only
very
10
20
30
40
O
2
(l)
→
2H
2
O(l)
+
O
2
reaction
can
be
followed
by
off
with
time
at
constant
measuring
the
volume
of
10.4.2
The
decomposition
hydrogen
oxygen

can
see
from
hydrogen
Figure
peroxide
10.4.2
does
not
peroxide
by
of
is
various
temperature.
metal
We
70
(g)
catalysed
given
60
(s)
2
Figure
The
50
slowly.
Time
2H
catalyst
0
catalyst
0
hydrogen
de
10
the
No
decomposition
) ox
er(
oxides.
that:
decompose
over
the
time-scale
of
the
DID
YOU
KNOW?
experiment
Most

manganese(IV)
oxide
and
lead( IV)
oxide
are
good
enzymes
reactions

copper(II)
oxide
is
a
less
effective
catalyst
than
manganese( IV)
lead(IV)
not
efficiently
catalyse
above
oxide
40 ºC
or
do
catalysts
because
the
structure
of
oxide.
the
so
enzyme
that
the
protein
changes
reactants
cannot
Enzymes
bind
Enzymes
are
biological
reactions
in
reactions
include:
the
cells
of
catalysts.
all
They
organisms.
are
proteins
Examples
of
that
catalyse
the
enzyme-catalysed
the
browning
enzyme.
above
reaction
when
some
fruits
are
say
is
to
At
about
structure
We

properly
the
surface
60 ºC
the
irreversibly
that
of
temperatures
the
enzyme
changed.
enzymes
are
cut
‘denatured’.

the
production
Figure
of
a
10.4.3
typical

The

Above
shows
how
by
increasing
enzyme-catalysed
40 ºC,
the
optimum
40 ºC,
rate
rate
the
fermentation.
increases
of
reaction
rate
the
temperature
affects
the
rate
reaction.
as
is
decreases
the
temperature
increases.
about
40 ºC.
as
temperature
the
increases.
noitcaer
Below
ethanol
desylatac-emyzne

of
fo
etaR
KEY
POINTS
1
The
rate
of
a
chemical
2
The
activation
reaction
increases
with
temperature.
10
energy
is
the
minimum
energy
the
20
30
40
50
Temperature
particles
must
have
to
react
when
they
Increasing
reactant
the
temperature
particles
having
increases
energy
(°C)
collide.
Figure
3
60
reactant
the
greater
proportion
than
the
of
activation
10.4.3
The
on
effect
the
of
rate
catalysed
temperature
of
an
enzyme-
reaction
energy.
4
A
catalyst
without
5
is
a
substance
getting
Enzymes
are
used
that
speeds
up
a
chemical
reaction
up.
biological
catalysts.
99
11
Energetics
11.1
Exothermic
and
endothermic
Exothermic
LEARNING
the
end
of
this
topic
be
exothermic
able
distinguish
and

between
energy
diagrams
use

describe

ΔH
for
exothermic
endothermic
reactions
energy
of
action
the
a
of
exothermic

the
reactions

the
neutralisation

the
combustion

dissolving
An
of
that
the
releases
energy
surroundings
to
increases.
changes:
acids
with
metals
reactions
of
of
of
acids
with
bases
fuels
metal
surroundings.
Examples
and
alkali
endothermic
the
to
exothermic
lowering
of
and
changes
demonstrate
in
reaction
exothermic
investigations
the
a
reactions
notation
describe
is
temperature
profile
endothermic

The
to:
endothermic
draw
reaction
surroundings.
Examples

reactions
you
the
should
endothermic
OUTCOMES
An
At
and
changes
of

the

dissolving
hydroxides,
reaction
The
a
changes
decomposition
sodium
reaction
temperature
endothermic
thermal
is
e.g.
of
of
that
the
hydroxide,
absorbs
in
energy
surroundings
water.
from
decreases.
include:
carbonates
catalysts
potassium
nitrate
or
ammonium
nitrate
in
water.
activation
reaction.
Enthalpy
An
changes
enthalpy
change
is
the
heat
energy
exchanged
between
a
chemical
a
reaction
and
its
surroundings
at
constant
pressure.
The
symbol
for
−1
Energy
enthalpy
change
is
ΔH.
The
unit
for
enthalpy
change
is
kJ mol
.
content
–1
)
(kJ mol
Figure
11.1.1
shows
energy
profile
diagrams
for
an
exothermic
and
NaOH (aq) + HCl (aq)
H
reactants
an
endothermic
reaction.
The
heat
energy
content
(enthalpy,
H)
of
Reactants
the
reactants
and
products
is
shown
on
the
vertical
axis.
The
reaction
–1
Δ H
=
–57.1 kJ mol
pathway
the
NaCl (aq) + H
is
shown
course
of
the
on
the
reaction
horizontal
as
you
go
axis.
The
from
reaction
reactants
to
pathway
shows
products.
You
O (l)
2
H
products
can
see
that
the
enthalpy
change
is
the
energy
difference
between
the
Products
heat
Reaction
energy
content
of
the
products
and
reactants.
athwa
enthalpy
change
=
energy
of
products
–
energy
of
reactants
b
For
an
exothermic
reaction:
Energy
content

the
energy
of
the
reactants
is
higher
than
the
energy
of
the
–1
(kJ mol
)
H
products
(g) + CO (g)
2
H
products
Products
–1
Δ H
H
=

so
energy

(energy

so
is
of
released
products
to
−
the
surroundings
energy
of
reactants)
is
a
negative
value
+131 kJ mol
ΔH
is
negative,
e.g.
O (g) + C (s)
2
H
reactants
−1
NaOH(aq)
Reactants
+
HCl(aq)
→
NaCl(aq)
+
H
O(l)
ΔH
=
−57.1 kJ mol
2
Reaction
Figure
11.1.1
Energy
a
b
100
an
an
pathway
profile
diagrams
exothermic
For
an
endothermic
reaction:
for

the

so
energy
of
the
reactants
is
lower
than
the
reaction,
endothermic
reaction
energy
is
absorbed
from
the
surroundings
energy
of
the
products

(energy

so
of
products
−
energy
of
reactants)
is
a
positive
value
DID
ΔH
is
positive,
YOU
KNOW?
e.g.
Y
ou
can
use
the
endothermic
−1
H
O(g)
+
C(s)
H
2
(g)
+
CO(g)
ΔH
=
+131 kJ mol
change
2
reduce
Activation
energy
and
the
effect
of
or
catalysts
order
for
particles
to
react
when
they
collide,
they
must
have
a
the
injury.
pack
In
in
‘cold
pain
In
(see
amount
10.4).
energy
of
energy.
Activation
that
the
This
energy
particles
is
must
is
called
always
acquire
the
activation
endothermic
and
react.
So
we
before
sometimes
call
they
the
because
are
able
it
to
is
barrier’
for
the
reaction.
We
can
extend
activation
our
to
include
activation
energy
a
(see
Figure
tube
nitrate.
tube
is
some
tube
is
broken
the
of
solid
Outside
the
energy
water
.
the
When
the
endothermic
collide
energy
between
the
ammonium
the
and
water
causes
a
profile
marked
diagrams
a
the
nitrate
‘energy
burn
type,
energy
change
successfully
a
to
a
ammonium
minimum
of
one
contains
pack’
decrease
in
temperature.
11.1.2).
b
Energy
Energy
content
content
Activation
energy
Reactants
Products
H
H
reactants
EXAM
TIP
products
Activation
energy
Δ H
Δ H
–ve
+ve
Mak
e
sure
arrows
Products
H
products
diag
reactants
co rrec
t
11.1.2
Energy
pathway
profile
exothermic
Reaction
diagrams
reaction,
b
including
an
activation
endothermic
energy
point
catalyst
remains
speed
is
a
substance
unchanged
up
reaction
a
at
reaction
by
that
the
speeds
end
because
decreasing
the
way.
for
a
fo r
Show
of
the
they
up
rate
reaction
lower
activation
the
the
of
(see
energ
y
an
In
reaction
10.4).
energy
energy.
barrier
Figure
but
and
pointin
g
Catalysts
to
the
11.1.3
we
ΔH
the
much
activation
lower
energy
than
for
for
the
the
catalysed
uncatalysed
fo r
an
Show
ΔH
the
fo r
an
reaction,
reaction,
E
E
react
ion
upwa
rds
arrow
(
↑).
fo r
exo th
ermic
see
pointin
g
(catalysed),
a
is
the
activ
ation
reaction
react
ion
that
profi
le
the
pathway
endo
therm
ic
A
the
energ
y
rams
arrows
Figure
that
Reactants
H
Reaction
in
down
ward
s
(
↓).
(uncatalysed).
a
Note
that
highest
KEY
1
2
the
point
activation
on
the
energy
arrow
goes
from
the
reactants
to
the
curve.
POINTS
Exothermic
reactions
release
Endothermic
reactions
The
change
enthalpy
exchanged
at
constant
between
of
a
energy
absorb
a
to
energy
reaction,
chemical
the
surroundings.
from
ΔH,
is
reaction
the
the
and
surroundings.
energy
its
Reactants
surroundings
E
pressure.
(catalysed)
a
E
(uncatalysed)
a
3
Energy
profile
reactants
4
For
an
and
diagrams
products
exothermic
show
the
plotted
reaction
energy
against
the
value
content
the
of
of
reaction
ΔH
is
Products
the
pathway.
negative.
For
an
Figure
endothermic
reaction
the
value
of
ΔH
is
11.1.3
Energy
for
5
Activation
energy
is
the
minimum
profile
amount
of
energy
that
an
with
exothermic
and
catalyst.
particles
6
Catalysts
must
are
have
in
order
substances
to
that
react
speed
when
up
a
they
chemically
without
E
collide.
reaction
without
changed.
Catalysts
speed
up
a
reaction
(catalysed)
activation
the
catalysed
energy
is
for
reaction.
(uncatalysed)
is
the
a
activation
7
reaction
a
a
the
E
being
diagrams
positive.
by
lowering
its
activation
energy.
energy
uncatalysed
for
the
reaction.
101
11.2
Energy
by
experiment
T
ypes
LEARNING
the
end
of
this
topic
be
enthalpy
change
able
describe
enthalpy
changes
(heat
changes)
according
to
the
type
you
of
should
of
OUTCOMES
We
At
changes
chemical
reaction
taking
place.
Three
examples
are:
to:
Heat
of
neutralisation,
ΔH
is
reaction
:
The
enthalpy
change
when
one
mole
n

describe
heat
of
neutralisation
of
and
heat
of
water
describe
by
the
of
an
acid
with
an
alkali
under
solution
standard

formed
conditions.
For
example,
the
neutralisation
of
the
strong
experiments
alkali
involving
sodium
hydroxide
with
the
strong
acid
hydrochloric
acid:
temperature
−1
NaOH(aq)
changes
+
HCl(aq)
→
NaCl(aq)
+
H
including
thermometric
O(l)
ΔH
2
titrations.
Heat
of
solution,
ΔH
:
The
enthalpy
=
−57.1 kJ mol
n
change
when
one
mole
of
a
sol
solute
is
under
standard
in
dissolved
which
no
example,
EXAM
in
a
solvent
conditions.
further
when
heat
sodium
to
By
form
an
‘infinitely
change
occurs
hydroxide
infinitely
dilute’
on
we
further
dissolves
in
dilute
solution
mean
a
solution
dilution.
excess
For
water:
TIP
−1
NaOH(s)
+
aq
→
NaOH(aq)
ΔH
=
−470 kJ mol
sol
Rem
embe
r
that
Heat
defini
tions
reaction,
chan
ges
reactants
shown
in
The
the
enthalpy
equation
change
react
to
when
give
the
molar
products
amounts
under
are
standard
alwa
ys
ΔH :
r
of
energ
y
of
invo
lving
compa
red
conditions.
For
example,
when
a
metal
reacts
with
an
acid:
unde
r
−1
Mg(s)
stan
dard
Stan
dard
1
cond
ition
s
atmos
phere
(760
mm
pressu
re)
+
2HCl(aq)
→
MgCl
cond
ition
s.
(aq)
+
H
2
We
are
pressu
re
can
whose
use
the
general
equation
is
term
(g)
ΔH
2
‘heat
of
=
−106.7 kJ mol
r
reaction’
for
any
reaction
given.
merc
ury
and
25 °C
.
Energy
We
changes
measure
apparatus
simple
When
to
enthalpy
called
polystyrene
a
the
from
cup,
experiments
(heat
energy)
a
calorimeter.
a
copper
can
A
or
a
change
simple
using
calorimeter
vacuum
flask.
a
piece
can
Figure
be
of
a
11.2.1
shows
calorimeter.
carrying
out
experiments
to
calculate
energy
changes
we
need
know:
Thermometer
Plastic

the
amounts
of

the
volume

the
temperature
of
reactants
in
moles
solvent
lid
Polystyrene
change
during
the
reaction.
cup
Finding
the
heat
of
neutralisation
by
experiment
(calorimeter)
To
find
the
enthalpy
change
of
neutralisation
of
sodium
hydroxide
by
Reaction
Stirrer
mixture
hydrochloric
acid:
−3
1
Place
a
known
hydroxide
Figure
11.2.1
A
polystyrene
used
as
a
measure
102
cup
can
calorimeter
enthalpy
in
a
volume
of
1.0 mol dm
polystyrene
cup
aqueous
sodium
(calorimeter).
be
2
Record
3
Add
the
temperature
of
the
aqueous
sodium
hydroxide.
to
changes.
−3
the
same
volume
of
1.0 mol dm
hydrochloric
acid
to
the
cup.
The
acid
should
be
at
the
same
starting
temperature
as
the
sodium
hydroxide.
4
Stir
the
reaction
mixture
and
record
the
highest
temperature
reached.
Finding
A
the
similar
heat
method
of
is
solution
used
to
by
find
experiment
the
heat
of
solution
of
sodium
DID
hydroxide
experimentally
(Figure
We
1
Place
a
known
volume
of
water
in
the
polystyrene
cup
Record
the
temperature
of
the
can
water.
a
Add
a
known
mass
of
sodium
hydroxide
to
the
find
a
Stir
the
reaction
mixture
and
record
the
The
highest
end
titration
point
when
the
acid
of
the
has
just
temperature.
by
the
curve
Sodium
point
reaction
water.
neutralised
the
alkali,
intersection
of
a
graph
of
of
is
shown
lines
in
the
temperature
Spatula
against
hydroxide
Thermometer
end
thermometric
7.7).
reaction,
4
the
neutralisation
using
(see
3
KNOW?
(calorimeter).
of
2
YOU
11.2.2).
KEY
volume
of
acid
added.
POINTS
3
1
100 cm
Polystyrene
water
Heat
of
neutralisation
is
the
cup
enthalpy
change
when
one
(calorimeter)
mole
the
Record
the
Add
temperature
of
Figure
the
mass
water
11.2.2
An
a
known
of
Record
sodium
the
temperature
to
find
the
heat
water
an
reached
alkali
under
of
solution
of
sodium
Heat
of
mole
alkali
metal
hydroxides
dissolve
in
water,
the
reaction
is
value
of
ΔH
is
salts
dissolve
of
endothermic,
in
water,
or
ammonium
depending
the
on
energy
the
salt.
change
When
can
be
a
a
solvent
of
ΔH
is
positive
decreases.
temperature
Finding
If
we
the
want
to
hydrochloric
the
heat
of
So
obtained
dissolves
in
water,
(endothermic).
heat
of
find
the
acid,
the
in
these
rather
cases
than
reaction
heat
of
heat
The
we
the
is
absorbed.
temperature
of
a
is
have
to
of
measure
metal
of
similar
with
a
the
standard
Heat
of
reaction
e.g.
change
amounts
acid
(an
100 cm
excess)
in
the
in
products
magnesium
to
the
4
with
method
give
standard
used
to
Energy
the
Record
the
temperature
of
the
Add
a
known
mass
of
of
react
a
under
changes
the
can
be
experimentally
temperature
known
amount
rise
of
2.0 mol dm
polystyrene
hydrochloric
magnesium,
equation
−3
,
cup
e.g.
and
known
volume
(calorimeter).
solution.
acid.
5
3
the
reactants
conditions.
measured
find
of
2
the
when
of
to
reactants
hydrochloric
is
shown
using
volume,
conditions.
lowest
solution.
known
an
solution
the
acid
3
Place
form
The
of
1
one
dissolved
highest.
reaction
method
is
nitrate
molar
solution
to
dilute
enthalpy
value
solute
the
when
exothermic
potassium
3
nitrate
is
change
negative.
under
or
standard
solution
infinitely
When
by
with
always
in
The
acid
hydroxide
enthalpy
exothermic.
formed
an
conditions.
2
When
is
of
highest
hydroxide
experiment
of
reaction
0.4 g,
to
the
hydrochloric
Thermometric
be
used
end
acid.
to
point
titrations
determine
of
an
can
the
acid–alkali
titration.
4
Stir
the
reaction
mixture
and
record
the
highest
temperature.
103
11.3
Calculating
energy
changes
Energy
LEARNING
The
At
the
end
of
this
topic
be
energy
able
is
transferred
calculated
calculate
as
using
experimental
results
heat
the
from
the
experiments
described
in
equation:
to:
q

from
you
11.2
should
changes
OUTCOMES
energy
=
m
×
c
×
ΔT
changes
where:
from
experimental
results
q

calculate
from
enthalpy
data
derived
m
from
understand
in
terms
c
enthalpy
of
bond
changes
making
energy
is
is
ΔT
the
mass
the
is
the
YOU
joules
(J)
in
grams
(g)
heat
in
capacity
in
joules
per
gram
per
ºC
(J g
−1
ºC
)
temperature.
using
this
equation
we
make
the
following
assumptions:
The
solution
losses
to
the
are
the
experiments
exothermic
Heat

The

The
density
to
to
is
the
same
specific
heat
capacity
as
water
of
a
in
the
dilute
solution
temperature,
is
the
ΔT,
same
as
assumes
that
that
of
water
there
are
(1.0 g cm
no
heat
surroundings.
involving
using
lost
Calculating
the
energy
change
by
Example
conduction
the
).
change
losses
major
reactions
calorimeters.
has
−1
ºC
−3
KNOW?
surroundings
in
solution
change
−1
error
of
specific
(4.2 J g
Heat
in
breaking.

DID
transferred
and
In
bond
the
−1
experiments

is
changes
1
calorimeter
,
3
thermometer
and
stirrer
,
When
by
−3
25 cm
of
hydrochloric
acid
of
concentration
1.0 mol dm
3
convection
to
the
air
and
is
by
added
to
25 cm
of
potassium
hydroxide
of
concentration
−3
radiation
from
calorimeter
.
flask
as
a
the
Using
walls
a
of
the
Calculate
vacuum
calorimeter
1.0 mol dm
,
the
the
temperature
heat
of
rises
neutralisation
from
for
21.1 ºC
this
to
27.3 ºC.
reaction.
reduces
KOH(aq)
+
HCl(aq)
→
KCl(aq)
+
H
O(l)
2
most
of
these
heat
losses.
−3
1
mass
of
solution
(assuming
density
−1
DID
YOU
When
two
a
KNOW?
reaction
different
occurs
2
specific
heat
3
temperature
4
heat
energy
capacity
change
=
released
4.2 J g
(27.3
q
=
between
compounds,
=
=
50
×
1.0 g cm
=
25 g
do
not
)
25 g
=
50 g
−1
21.1) ºC
×
c
4.2
×
×
=
6.2 ºC
ΔT
6.2
=
1302 J
the
concentration
compounds
+
ºC
–
m
=
separate
into
5
number
of
moles
of
acid
×
volume
=
1000
individual
atoms.
Sometimes
1.0
one
particular
bond
breaks
and
×
25
=
=
0.025 mol
1000
then
a
forms
different
bond
one
a
atom.
starts
breaks.
happens
is
new
bond
Sometimes
forming
The
as
way
called
with
the
a
6
1302 J
7
So
the
energy
is
released
by
0.025 mol
HCl
for
1 mol
of
HCl
(and
1 mol
of
water
formed)
energy
released
this
1
mechanism
1302
of
of
another
reaction.
×
=
52 080 J
0.025
−1
So
ΔH
=
n
104
−52 kJ mol
(to
2
significant
figures)
is
).
Example
2
EXAM
When
0.5 g
of
sodium
hydroxide,
NaOH,
is
dissolved
completely
TIP
in
3
200 cm
of
water,
the
temperature
of
the
solution
rose
from
21.4 ºC
T
he
to
28.4 ºC.
Calculate
the
heat
of
solution
of
sodium
hydroxide.
when
−1
mass
of
NaOH
=
40 g mol
energ
y
relea
sed
(Molar
sulfu
ric
)
neut
ralis
ed
acid
by
sodium
−3
1
mass
of
solution
(assuming
density
=
1.0 g cm
)
=
200 g
hydr
oxide
−1
2
specific
heat
capacity
=
4.2 J g
−1
In
ºC
this
water
3
temperature
4
heat
change
=
(28.4
–
21.4) ºC
=
released
q
=
m
×
c
×
is
−112.
6 kJ.
react
ion
are
+
H
ΔT
Na
4
SO
2
=
200
×
4.2
×
7.0
=
So
of
moles
of
NaOH
2H
O
2
taken
=
=
molar
the
heat
of
0.5
–2
number
+
4
5880 J
mass
5
of
SO
2
→
q
2 mo
l
produc
ed.
7.0 ºC
2NaO
H
energy
is
=
mass
1.25
×
10
neut
ralis
ation
mol
(whi
ch
is
40
per
mo le
of
water
fo rm
ed)
−2
6
5880 J
7
So
for
of
energy
1 mol
of
is
released
NaOH
by
energy
1.25
×
released
10
mol
NaOH
is
half
this
valu
e:
−1
−56
.3 kJ
mo l
is
1
5880
×
=
470 400 J
–2
1.25
×
10
−1
So
ΔH
=
−470 kJ mol
(to
2
significant
figures)
KEY
POINTS
sol
1
Bond
making
and
bond
The
a

An
input
of
energy
is
needed
Energy
is
to
break
bonds.
So
bond
breaking
using
is
q
released
when
energy
reaction
endothermic.

heat
given
out
in
breaking
bonds
are
formed.
So
bond
making
the
=
can
be
calculated
equation
m
×
c
×
ΔT
is
2
In
calculating
enthalpy
exothermic.
changes

In
an
endothermic
bonds
in
the
reaction,
reactants
more
than
is
energy
given
out,
is
needed
making
to
new
break
bonds
the
in
results
from
we
experimental
assume
that:
the

the
solution
has
the
same
products.
specific

In
an
exothermic
reaction,
more
energy
is
released
on
forming
heat
capacity
as
new
water
bonds
in
the
products
than
is
needed
to
break
the
bonds
in
the

the
density
of
a
dilute
reactants.
solution
that
Bond
energy
The
energy
the
same
as
water
calculations


of
is
needed
to
break
a
covalent
bond
between
two
there
particular
from
are
the
no
heat
losses
apparatus.
−1
atoms
is
called
the
bond
energy,
e.g.
E(H − H)
−1
E(O = O)
=
498 kJ mol
=
436 kJ mol
,
3
−1
,
E(O − H)
=
464 kJ mol
.
We
can
use
Bond
breaking
endothermic.
energies
to
calculate
the
energy
change
in
a
For
example,
consider
the
(g)
+
O
2
(g)
→
2H
2
bonds
broken
in
exothermic.
reactants
The
ΔH
a
bonds
positive)
energy
formed
in
×
2
×
E(H − H)
(exothermic,
ΔH
+
E(O = O)
+
498
4
×
4
×
bond
a
broken
=
between
covalent
two
atoms
compound
the
bond
is
energy.
E(O − H)
The
overall
in
reaction
enthalpy
change
464
−1
bonds
break
negative)
5
436
to
products
called
2
required
O(g)
2
in
(endothermic,
making
reaction:
4
2H
Bond
reaction.
is

is
bond
a
depends
on
−1
+1370 kJ mol
bonds
formed
=
−1856 kJ mol
the
difference
in
the
bond
−1
The
exothermic
change
is
greater
by
(1856
–
1370) kJ
=
486 kJ mol
.
energies
the
of
particular
reactants
and
bonds
in
products.
−1
So
the
enthalpy
change
is
–486 kJ mol
.
105
Section
Objectives
A7–11
1
the
A
Summary
questions
−3
Calculate
solution
concentration
containing
2 g
of
in
mol dm
sodium
of
a
soil
hydroxide,
is
at
the
same
time,
especially
if
the
ground
moist.
3
NaOH,
in
50 cm
of
solution.
11
(A :
H
=
1,
O
=
16,
Na
=
State
a
use
for
each
of
the
following
23)
r
compounds:
2
Calculate
the
mass
of
potassium
nitrate,
KNO
,
3
a
calcium
carbonate
b
sodium
chloride
c
calcium
sulfate
d
sodium
benzoate.
3
in
20 cm
of
a
solution
of
potassium
nitrate
of
–3
concentration
(A :
N
=
14,
0.40 mol dm
O
=
16,
K
=
12
39)
Describe
how
you
could
determine
the
end
r
3
A
solution
of
potassium
concentration
was
hydroxide
titrated
with
of
+
H
SO
2
→
K
4
SO
2
+
2H
4
required
of
using
pH
neutralisation
reaction
without
changes
or
an
acid–base
indicator.
acid.
Define
oxidation
and
reduction
in
terms
of:
O
a
–3
15 cm
a
2
3
It
of
unknown
sulfuric
13
2KOH
point
0.10 mol dm
oxidation
number
b
electrons.
sulfuric
3
acid
to
neutralise
hydroxide
25 cm
of
the
potassium
14
Deduce
the
oxidation
number
of:
solution.
a
Fe
in
FeCl
b
P
in
P
3
O
2
5
Calculate:
c
S
in
Na
SO
2
a
the
number
of
moles
of
sulfuric
acid
d
N
in
the
NO
3
ion
3
used
e
S
in
Na
S.
2
in
the
titration
15
b
the
concentration
of
the
Identify
the
potassium
the
mass
of
potassium
hydroxide
20 cm
of
potassium
Cl
and
reducing
agents
in
equations.
+
2NaI
→
I
2
present
3
in
oxidising
following
hydroxide
a
c
the
aqueous
b
hydroxide.
+
2NaCl
2
CO
+
ZnO
→
Zn
+
CO
2
+
c
4
Define
a
the
terms
pH
acid
b
and
base
proton
in
terms
What
is
meant
by
the
16
transfer.
weak
acid
b
+
2I
an
example
with
each
relevant
these
Question
Describe
crystals
from
how
of
the
you
and
potassium
+
questions
about
I
2
the
equations
Which
species
illustrate
Give
in
a
equation
reason
15a
for
gets
your
answer.
your
Which
species
in
equation
15b
gets
equations.
would
soluble
O
15.
reduced?
6
2H
base?
b
answers
→
terms
strong
of
2H
2
oxidised?
Give
+
2
Answer
a
a
O
2
of:
in
5
H
prepare
salt
pure
potassium
hydroxide
using
a
dry
c
chloride
Which
Give
species
change
in
a
in
reason
for
equation
oxidation
your
15c
answer.
does
not
number?
titration
17
A
dilute
aqueous
solution
of
LiCl
is
method.
electrolysed
7
Lead
iodide
is
an
insoluble
salt.
Describe
would
prepare
a
pure
dry
sample
carbon
electrodes.
how
a
you
using
of
Explain
why
an
aqueous
solution
of
LiCl
lead
conducts
electricity
but
solid
LiCl
does
not
iodide.
conduct.
8
State
the
basic
oxide,
oxide,
difference
an
giving
between
amphoteric
an
example
an
acidic
oxide
of
and
oxide,
a
a
b
neutral
State
Write
a
sodium
10
Explain
balanced
why
ammonium
106
equation
hydroxide
lime
salts
with
and
for
the
reaction
ammonium
fertilisers
should
not
names
of
the
products
formed
at
each.
i
9
the
the
be
of
in
sulfate.
containing
added
to
the
anode
this
for
c
At
electrolysis
these
which
place?
ii
and
cathode
write
half
equations
reactions.
electrode
Explain
your
is
oxidation
answer.
taking
18
Electrolysis
sodium
of
a
concentrated
chloride
produces
solution
chlorine
at
of
24
Zinc
reacts
with
aqueous
copper(II)
the
Zn(s)
+
CuSO
(aq)
→
ZnSO
4
anode
and
hydrogen
at
the
sulfate.
(aq)
+
Cu(s)
4
cathode.
–1
ΔH
a
Explain
why
hydrogen
is
formed
at
a
cathode
and
not
=
Is
this
Explain
why
chlorine
is
formed
at
and
not
Describe
and
electrolysis
explain
of
the
aqueous
differences
copper( II)
in
(graphite)
a
reason
the
for
your
information
Explain
the
sulfate
about
endothermic?
in
answer
the
by
referring
equation.
electrodes
and
active
your
bond
answer
to
making
part
and
a
using
bond
ideas
breaking.
using
c
inert
or
oxygen.
b
19
exothermic
the
to
anode
reaction
sodium.
Give
b
–212 kJ mol
the
Draw
a
labelled
energy
profile
diagram
for
(copper)
this
reaction.
electrodes.
25
20
During
the
electrolysis
of
copper( II)
The
heat
when
solution,
copper
is
deposited
at
the
a
of
the
mass
of
copper
0.2 amps
flows
deposited
for
1 h
of
a
is
the
energy
substance
is
change
dissolved
in
cathode.
solvent
under
standard
conditions.
when
a
current
solution
1 mol
excess
Calculate
of
sulfate
Describe
how
you
would
carry
out
an
25 min.
experiment
to
calculate
the
heat
of
–1
(A :
Cu
=
63.5;
F
=
96 500 C mol
)
solution
of
potassium
nitrate
in
water.
r
b
21
Calculate
the
volume
of
oxygen,
at
When
using
produced
is
at
the
electrolysed
anode
for
when
40 min
acidified
using
a
calculating
the
the
1:
ionises
slightly
to
solution
water
current
of
energy
=
mass
×
specific
×
Water
of
relationship
2.5 amps.
(Hint
heat
r.t.p.,
form
OH
and
what
assumptions
heat
capacity
temperature
would
you
change
make?
+
H
ions.
26
Hint
2:
4OH
→
O
(g)
+
2H
2
O(l)
+
4e
Iron(II)
sulfate
for
oxidising
sulfate
22
Define:
a
rate
of
reaction
b
contains
can
agents.
Large
marble
chips
(calcium
carbonate)
24 °C.
by
with
27
The
1.0 mol dm
course
measuring
of
the
the
hydrochloric
reaction
volume
of
was
carbon
acid
be
Define
the
used
to
an
show
that
oxidising
potassium
agent.
followed
a
electrode
b
cation
c
electrolysis.
dioxide
A
Draw
a
labelled
diagram
of
the
spoon
made
from
nickel
can
be
could
be
with
Draw
a
labelled
one
other
way
of
measuring
of
this
reaction
that
does
not
the
volume
of
carbon
with
how
the
following
would
speed
of
show
this
reaction.
In
a
the
nickel
silver.
Write
the
half
each
at
equations
i
the
for
anode
the
ii
reactions
the
cathode.
affect
c
the
to
electroplate
dioxide.
occurring
Describe
to
involve
b
measuring
used
the
spoon
course
diagram
used.
apparatus
Describe
silver.
apparatus
a
c
is
off.
that
b
test
terms:
electroplated
a
to
iron( II)
at
28
given
used
how
were
–3
reacted
be
Suggest
catalyst.
manganate(VII)
23
can
)
2
Give
two
reasons
why
articles
are
case,
electroplated.
assume
all
other
factors
are
kept
the
same.
29
–3
i
Using
0.05 mol dm
ii
Using
smaller
hydrochloric
Write
a
marble
equations
Carrying
out
the
reaction
at
Sketch
a
curve
to
show
The
reaction
dioxide
changes
how
the
volume
to
explain
how
with
the
The
reaction
time.
Use
with
copper
oxide,
of
calcium
CuO,
with
rate
of
hydroxide
with
acid.
this
The
reaction
of
sodium
hydrogencarbonate
reaction
with
changes
of
of
c
curve
reactions:
acid.
hydrochloric
carbon
following
22 °C
b
d
the
chips
sulfuric
iii
for
acid
hydrochloric
acid.
time.
107
Section
SECTION
1
Which
A:
of
mixture
a
A
Practice
Multiple-choice
the
of
following
clay
and
exam
questions
questions
best
describes
a
5
water?
Which
of
Solution
a
a
of
the
following
standard
A
solution
whose
accurately
b
Suspension
c
Colloid
d
Homogeneous
b
A
Which
of
the
following
is
a
common
use
the
best
definition
concentration
is
concentration
is
known
solution
whose
determined
2
is
solution?
through
c
A
solution
obtained
d
A
solution
that
volumetric
following
analysis
titration
of
is
added
into
the
burette
carbon-14?
during
a
To
make
a
nuclear
b
To
generate
a
titration
bomb
6
Which
of
the
composition
c
To
following
is
the
percentage
electricity
determine
the
age
of
animal
and
by
mass
of
oxygen
in
copper( II)
plant
sulfate?
remains
(A :
Cu
=
64;
S
=
32;
O
=
16)
r
d
To
provide
a
power
source
for
heart
a
10%
b
16%
c
40%
d
64%
pacemakers
3
Which
of
the
arrangement
react
most
following
of
the
is
the
Group
vigorously
with
II
electron
element
dilute
that
will
hydrochloric
acid?
7
4
Which
of
the
following
a
2,8,8,2
preservation?
b
2
a
Sodium
nitrite
c
2,8,2
b
Sodium
chloride
d
2,2
c
Sodium
benzoate
d
Sodium
carbonate
Element
of
the
X
has
an
following
atomic
number
statements
is/are
of
7.
true
Atoms
ionic
of
element
X
can
engage
in
bonding.
Atoms
When
substance
of
element
acidified
solution
When
X
can
engage
metallic
Atoms
is
added
to
a
solution
changes
iron(II)
salt,
to
I
only
b
I
and
II
c
I
and
III
d
I,
the
element
bonding.
X
can
engage
only
of
the
added
solution
following
a
Acidified
K
Cr
b
Acidified
c
Dilute
d
Conc.
H
O
HNO
H
SO
2
O
2
3
only
III
is
in
2
and
Y
purple
to
to
a
the
colourless.
solution
changes
from
yellow.
2
a
from
manganate( VII),
bonding.
of
covalent
108
Y
potassium
substance
Which
II
food
in
green
III
in
of
an
II
used
X?
of
I
not
Which
8
element
is
4
2
7
is
substance
Y?
of
pale
SECTION
9
a
A:
Name
the
i
Short
the
answer
processes
following
which
notices
on
underside
cover
a
best
describe
ii
observations:
Steven
the
questions
pot
of
that
hot
be
water
of
Predict
the
has
lid
collected
used
iii
to
the
major
recorded
Explain
using
preparation,
soup.
yield
of
the
ii
Blue
crystals
turn
water
of
copper( II)
from
sulfate
colourless
to
your
why
salt
percentage
observations
during
actual
only
for
that
will
reaction.
knowledge
the
is
yield
this
1%
CaCl
slowly
of
(3)
salt
percentage
while
is
the
85%.
(5)
2
blue.
e
Give
one
industrial
use
of
calcium
carbonate.
iii
Mothballs
decrease
becoming
liquid.
in
size
(3)
11
b
What
and
method
retain
would
the
you
following
use
to
separate
Redox
the
substances?
reactions
industrial
industrial
reactions
i
Water
from
ii
Pure
water
iii
Barium
(1)
without
are
process
is
used
on
preparation
that
a
of
large
occurs
because
from
sulfate
tap
from
a
Define
sodium
electrolysis.
b
Below
the
term
redox
reaction.
is
an
ionic
equation
representing
the
following
and
+
2Ag
iii
Cation
iv
Electrons
Identify
the
in
in
of
a
potassium
atom
+
2Ag(s)
explain
agent
your
in
this
answer
oxidation
in
Given
that
numbers.
(3)
a
potassium
Examine
can
ion
the
undergo
a
flowchart
an
excess
of
silver
solution
and
added
to
5 g
of
copper,
calculate
(8)
the
carbonate
reactions.
reducing
and
terms
was
Calcium
(aq)
anion
ii
10
Cu
ion
and
electrons
→
compound
reaction
and
2+
(aq)
pairs:
i
Atom
a
reaction:
+
ii
(1)
(4)
between
Element
redox
chloride
Cu(s)
i
of
water
redox
Distinguish
in
One
rum
solution
c
scale
substances.
variety
below
mass
formed
of
and
(A :
Cu
of
silver
from
this
Ag
that
would
be
reaction.
=
64;
=
108)
of
0.5 mol dm
(3)
r
use
it
to
answer
the
questions
which
follow.
3
12
a
–3
26.50 cm
sulfuric
acid
3
calcium
oxide
+
carbon
were
dioxide
needed
potassium
Heat
Solid
calcium
to
carbonate
+
CaCl
X(aq)
(aq)
+
A
+
neutralise
hydroxide.
calculate
potassium
B
to
the
Use
molar
hydroxide
SO
of
information
concentration
of
solution.
3
2
this
(5)
2
+
H
25.00 cm
b
i
25 cm
–3
of
2.64 mol dm
hydrochloric
(aq)
3
4
acid
is
reacted
with
50 cm
of
–3
1.32 mol dm
Salt
a
Write
state
+
a
A
+
a
sodium
solution
in
that
temperature
hydroxide
polystyrene
balanced
symbols
to
chemical
represent
equation
the
the
25 °C
with
to
37 °C,
neutralisation.
heating
rose
calculate
(Specific
–1
(thermal
decomposition)
of
Name
c
Suggest
(2)
products
the
of
calcium
carbonate.
b
A
name
and
of
B.
ii
X.
(1)
How
iii
List
i
Name
the
salt
formed
when
=
does
expected
(2)
reactant
water
two
would
d
cup.
Given
B
4.18 J g
this
reacts
with
H
SO
2
the
heat
heat
of
capacity
–1
°C
)
compare
(5)
with
value?
have
been
the
(1)
assumptions
which
made
during
this
calcium
experiment.
carbonate
value
from
(aq).
(2)
(1)
4
109
Organic
an
chemistry:
introduction
12.1
Organic
Organic
LEARNING
end
of
this
topic
compounds
compounds
be
able
understand
can
that
form
may
organic
the
carbon
terms
of
of
or
branched
chains
they
organic
for
Compounds
the
H
H
−
−
C
−
C
C
atoms.
ethane
may
and
be
with
only
H
H
−
H
We
are
called
bonds
different
may
also
double
Figure
types
classify
12.1.2
−
or
organic
their
are
molecules
ethane
triple
and
bonds
compounds.
compounds
branched
shows
the
structures
−
C
C
are
bonds
called
propane
(in
addition
(see
to
Examples
are
according
chains
and
to
ring
single
ethene
their
structure
structures.
of
unbranched,
branched
and
Hydrocarbons
hydrogen
=
C
−
−
b
−
H
a
H
Jöns
organic
Pentane
H
H
−
is
an
unbranched
hydrocarbon,
c
C
−
C
H
H
and
two
hydrocarbon,
cyclopentane
is
b
a
H
2-methylbutane
ring
is
a
hydrocarbon.
types
of
formulae
main
inorganic.
burn
We
can
represent
formulae.
Using
organic
butane,
molecules
C
H
4
when
and
using
a
butene,
variety
C
10
H
4
of
as
different
examples:
8
heated.

inorganic
−
C
Berzelius
into
compounds
black)
C
H
H
Swedish
Different
chemicals
−
H
H
C−
C
−
H
called
a
H
H
branched
ago,
−
C
−
−
12.1.2
−
−
Figure
H
C
−
H
−
C
−
compounds.
−
C
H
H
−
C
are
H
−
−
−
−
−
−
propene
−
and
KNOW?
years
H
C
−
H
−
−
H
−
−
−
Ethene
H
C
−
H
H
−
−
are
compounds.
unsaturated
(go
only
H
−
propane
C
−
and
−
C
−
Ethane
−
−
−
a
organic
containing
c
H
H
H
H
200
compounds
−
a
−
12.1.1
are
atoms.
−
H
−
and
propene
b
chemicals
The
molecular
formula
shows
the
number
of
each
melt
present
in
one
molecule
of
the
compound:
decompose.
butane
C
H
4
110
of
H
saturated
or
type
structure
H
Most
the
the
5.2.4.
12.1.1(b)).
of
chains,
hydrocarbons.
carbon
H
char
to
of
and
−
H
ethene
or
5.2.3
share
−
−
C
H
H
Most
can
structure
Figures
according
atom
H
−
−
H
groups:
carbon
electronic
see
in
Examples
unsaturated
(see
unbranched
ring
divided
the
a
H
H
chemist
For
ethene,
So
propane
b
About
2,4.
classified
single
containing
propene
Figure
YOU
is
−
−
−
−
−
H
ethane
−
other
carbon
−
H
H
as
DID
atoms
atoms.
H
−
−
−
−
−
C
of
compounds.
Compounds
Three
Figure
hydrogen
halogen
term
H
=
or
group.
and
C
nitrogen
12.1.1(a)).
bonds)
H
oxygen,
simple

−
e.g.
compounds
functional
C
atoms,
and
formulae
understand
−
with
compounds
Figure
H
organic
contain.
saturated
H
All
contain
unsaturated?
compounds
Organic
rings

a
other
structure
electrons
carbon
chains,
and
electronic
four
compounds
condensed
displayed

things.
usually
H
write
contain
Saturated
and
structures
unbranched

living
bonds
describe
in
all
They
carbon
single
The

of
−
double
basis
atoms.
−
atoms
the
carbon
to:
and

contain
H
should
are
you
H
the
compounds
OUTCOMES
Organic
At
structures
H
12
butene
10
C
H
4
8
type
of
atom

The
condensed
atom
in
a
formula
molecule
as
shows
well
as
the
the
atoms
position
bonded
of
any
to
each
double
or
carbon
EXAM
No t
bonds:
CH
CH
3
CH
2
CH
2
3
all
organi
c
butene
Carb
on
The
displayed
formula
shows
all
are
atoms
and
all
bonds
present
compo
unds
.
mon
oxide,
carbon
in
dioxid
e,
the
carbon
3
butane

compo
unds
contai
ning
CH = CHCH
CH
3
TIP
triple
carbon
ates
molecule.
and
hydr
ogen
carbon
ates
H
H
H
H
−
−
H
as
are
inorga
nic
compo
unds
.
−
−
H
class
ified
H
H − C − C = C − C − H
−
−
−
−
H
H
−
−
−
−
−
−
H − C − C − C − C − H
H
H
H
H
H
butane
butene
a
The
or
formulae
above
space-filling
structure
of
group
atoms
them
of
or
that
is
in
organic
help
two-dimensional.
to
show
us
(Figure
the
Ball-and-stick
models
three-dimensional
12.1.3).
groups
are
contain.
two
only
molecules
compounds
they
A
carbon
classified
functional
atoms
characteristic
functional
− OH
models
organic
Functional
Organic
are
groups
alcohols
of
functional
group
a
a
is
of
in
compounds
group
C = C
acids.
on
a
bond
in
the
Examples
alkenes,
Different
groups.
b
of
between
compounds.
are:
functional
depend
functional
triple
organic
alkanoic
the
atom,
or
compounds
different
to
an
double
class
organic
have
organic
of
with
− COOH
and
compounds
properties
in
according
group
classes
The
of
chemical
properties
of
the
Figure
or
groups
that
they
12.1.3
a
Ball-and-stick
butane,
model
EXAM
KEY
Saturated
single
organic
compounds
contain
only
bonds.
Unsaturated
or
writt
en
triple
organic
compounds
contain
one
or
more
double
Organic
compounds
chains
or
can
exists
as
unbranched
T
he
molecular
formula
shows
the
number
of
each
type
of
in
a
bo th
fo rm
ula
A
condensed
formula
for
an
organic
compound
shows
can
bonded
to
each
carbon
atom
in
a
molecule
as
well
position
of
any
double
or
triple
are
and
A
displayed
formula
shows
all
the
atoms
and
bonds
in
a
molecule.
7
A
functional
characteristic
of
a
is
an
class
atom
of
or
group
organic
just
of
atoms
that
is
the
fo rm
ula
it
group
the
fo rm
ula.
aske
d
bonds.
write
6
used
If
as
you
the
be
cond
ensed
the
displa
yed
atoms
3
struct
ural
the
molecule.
CH
2
atom
fo r
the
e,g,
CH
2
term
all
be tw
een
CH
fo rm
ula
A
some
times
atom
s,
chains,
rings.
is
bond
s
carbon
bonds.
branched
5
ethene
show
ing
3
4
of
cond
ensed
CH
3
of
space-filling
TIP
fo rm
ula
carbon–carbon
the
2
b
POINTS
T
he
1
model
contain.
is
best
to
struct
ural
fo r
to
displa
yed
your
write
exam
,
the
fo rm
ula.
compounds.
111
12.2
Homologous
formulae
series:
and
nomenclature
Homologous
LEARNING
A
At
the
end
of
this
topic
homologous
be
able
describe
the
functional
characteristics
can
homologous
be
represented
H
n
write
the
general
molecular
alkanes,
of
deduce
series
formulae
and
compounds
of
the
that
same
all
contain
homologous
the
series:
by
a
alkane
general
formula.
homologous
series
For
has
example,
the
each
general
formula
+
n
is
the
number
of
carbon
atoms.
2

have
the

differ
same
functional
group
for
alcohols
from
the
members
immediately
before
or
after
by
a
CH
and
group
2

acids
the
the
where
2n
have
similar
functional

of
members
and
alkenes,
alkanoic
group
series
C

a
The
of
member
a
is
group.
to:


series
you
same
should
series
OUTCOMES
chemical
properties
(because
they
have
the
same
group)
homologous
given
the
condensed
fully
displayed
formulae

show
a
gradual
carbon
of
atoms
change
in
the
in
physical
compounds
properties
as
the
number
of
increases.
compounds
T
able

write
and
fully
displayed
names
of
structures
alkenes,
alcohols
that
be
the
functional
attached
T
able
a
to
hydrogen
to
an
12.2.1
alkyl
alter
nativ
e
nam
e
an
group
alkyl
for
fo r
atom.
Homologous
Functional
group
series
− CH
group
,
of
an
and
− C
alkanoic
H
2
,
etc.
acids
(see
5
alcohol
can
only
to
C
ethane
CH
2n+2
CH
3
3
H
H
is
alkene
−
acids.
C
−
acids
C
=
C
H
n
ethene
2n
=
CH
CH
2
2
alka
nes
carbon
7
=
alcohol
−
=
−
O
C
H
H
n
OH
ethanol
CH
2n+1
CH
3
OH
2
hept-,
alkanoic
9
−
C
nam
e
10
H
H
fo r
are:
oct-,
Example
−
atom
s
acid
C
H
n
O
non -,
COOH
CH
2n+1
COOH
3
=
−
10
=
C
draw
ing
struct
ures
remem
ber
fo rm
s
doub
le
112
Naming
straight
chain
organic
compounds
carbon
error
It
is
to
a

naming
joine
d
bond
.
The
first
carbon
organic
compounds:
part
of
atoms
the
name
present
in
(the
the
stem)
longest
depends
chain
of
on
the
carbon
number
atoms
of
(see
draw
also
hydr
ogen
attach
ed
atom
s
H
bond
s
itself
.
man
y
−
the
alkene
s,
When
comm
on
C
of
that
four
arou
nd
atom
s
acid
dec-.
When
too
ethanoic
−
O

be
−
stem
s
7
General
n
unbr
anch
ed
=
alkenes
as
formula
−
carbox
ylic
8
will
series
An
alka
noic
with
such
− OH
The
−
alter
nativ
e
T
he
you
group.
−

series
alcoho
ls
alka
no ls.
fo r
homologous
alkanes,
group
alkane
is
the
TIPS
Homologous
An
of
3
or
attached

examples
acids.
12.3)
EXAM
some
and
must
alkanoic
shows
unbranched
Note
alkanes,
12.2.1
study.
12.3),
atoms
to
by
e.g.
and
meth-
prop-
for
for
one
three
carbon
carbon
atom,
eth-
for
two
carbon
atoms.
the

The
second
part
of
a
functional
group:
the
name
(the
suffix)
usually
depends
on
the
-ane
for
alkanes
-ene
for
alkenes
DID
-ol
for
alcohols
-oic
acid
for
alkanoic
YOU
Over
Alkanes
are
saturated
hydrocarbons
which
can
exist
KNOW?
acids
as
4
million
compounds
chains
or
branched
12.2.2
are
Names
and
structures
of
the
first
six
alkanes
past
over
10
years
500 000
compounds
Stem
Number
Name
of
molecular
carbon
atoms
meth-
known.
In
chains.
the
T
able
organic
unbranched
and
Displayed
alone,
new
have
organic
been
made.
formula
formula
1
methane,
H
−
CH
4
H
−
−
C
a
H
−
CH
CH
=
CH
3
CH
2
=
CH
CHCH
3
3
H
H
H
−
−
C
−
−
−
H
H
H
H
C
H
−
C
−
=
C
H
−
C
−
H
propane,
H
−
C
−
−
C
C
−
H
H
−
−
H
H
H
CH
OH
CH
3
−
−
−
−
H
−
−
C
C
C
−
H
−
−
−
−
H
H
−
H
H
−
−
C
H
5
pentane,
H
H
H
H
−
12
H
−
C
−
−
C
C
−
C
−
H
C
CH
H
H
H
H
−
−
H
−
C
−
−
C
C
−
C
−
−
H
H
shows
examples
of
condensed
and
displayed
CH
alkanoic
acids
CH
2
−
C
H
H
−
C
−
C
−
C
−
O
C
−
−
−
−
O
H
H
pentanoic
Members
of
functional
the
same
group
and
homologous
general
series
formula
have
and
the
have
Successive
the
H
acid
similar
12.2.1
Names
and
structures
properties.
of
from
−
H
same
Figure
chemical
2
H
POINTS
H
1
COOH
2
−
H
KEY
CH
2
−
and
acid
−
alcohols
H
formulae
−
alkenes,
=
ethanoic
−
some
−
H
H
of
O
O
3
12.2.1
C
H
CH
Figure
H
H
−
C
−
H
C
−
−
−
−
−
H
H
H
COOH
−
C
H
−
−
−
−
14
H
H
H
H
6
−
−
H
H
−
C
O
3
H
−
hexane,
−
c
−
−
6
C
butan-1-ol
H
hex-
−
−
−
−
−
−
H
H
C
H
H
H
5
−
H
−
−
−
−
C
C
H
H
methanol
pent-
H
−
C
H
OH
2
−
−
−
−
H
O
CH
2
H
H
−
−
10
C
−
H
4
−
CH
2
−
H
CH
3
−
H
−
H
−
H
−
butane,
C
H
b
8
−
4
−
but-2-ene
H
but-
C
−
−
H
3
−
H
−
C
C
H
=
3
=
H
propene
prop-
C
−
C
−
−
H
−
H
−
6
H
−
H
H
2
−
−
−
C
H
H
H
−
H
H
−
ethane,
−
2
−
eth-
members
next
by
a
in
CH
the
same
group
homologous
and
show
a
series
gradual
b
differ
change
some
a
alkenes,
alcohols,
c
alkanoic
acids
in
2
physical
3
4
properties.
Organic
compounds
number
of
The
stem
carbon
prop-
carbon
names
atoms
(3),
in
are
but-
are
named
atoms
organic
shown
(4),
in
pent-
in
the
using
a
longest
compounds
brackets)
(5),
hex-
stem
showing
unbranched
(the
are
number
meth-
(1),
the
chain.
of
eth-
(2),
(6).
113
12.3
Isomers
and
their
nomenclature
Isomers
LEARNING
OUTCOMES
Compounds
At
the
end
of
this
topic
formulae
should
be
able
are
write
fully
displayed
names
of
alkenes
Chain
isomerism:
For
The
example,
methylpropane,
structural
write
the
fully
different
of
structural
structural
structure
of
the
carbon
skeleton
butane
C
H
of
,
has
but
the
same
butane
has
molecular
an
formula
unbranched
chain
10
methylpropane
has
a
branched
chain
(Figure
12.3.1).
displayed

structures
isomers
Position
molecular
isomerism:
The
position
of
the
functional
group
differs.
given
For
their
but
types
isomerism
whereas

T
wo
are:
4
define
formula
isomers.
alkanes
as

molecular
and
differs.
branched
same
structural
structures

and
the
called
to:
isomerism

with
you
example,
the
position
of
the
double
bond
in
pent-1-ene
is
formulae.
different
from
the
position
in
pent-2-ene
(Figure
12.3.2(a)).
a
H
H
−
H
=
C
−
C
C
H
H
H
H
−
−
H
−
−
H
C
−
H
−
C
−
−
−
−
−
−
C
−
−
C
H
H
−
−
C
−
−
−
C
−
=
H
H
H
H
−
H
C
H
H
−
−
C
−
−
−
H
H
−
C
H
−
−
C
H
−
−
C
−
−
H
H
−
−
−
H
H
−
H
H
H
pent-1-ene
pent-2-ene
butane
−
H
−
−
C
H
C
−
H
H
−
H
H
O
H
H
−
H
−
H
C
−
C
H
−
C
−
O
−
−
−
−
−
H
H
−
C
−
−
C
−
−
H
−
−
H
C
−
C
−
−
−
C
−
C
−
−
−
−
H
H
H
H
−
−
−
H
H
−
C
−
−
−
H
H
−
−
−
H
H
H
H
H
b
H
butan-1-ol
butan-2-ol
H
Figure
12.3.2
Position
isomerism:
a
two
position
isomers
of
pentene,
methylpropane
b
Figure
two
position
isomers
of
butanol
12.3.1
Naming
The
chains
branched

Alkyl
branched
that
come
chain
groups
chain
off
the
compound
have
the
isomers
side
are
of
the
called
general
longest
alkyl
formula
C
We
name
− CH
is
alkyl
groups
− C
methyl,
3
The

H
C
H
−
−
C
H
−
H
chain
C
−
−
Longest
C
compound

H
Look
side

for
is
the
chain
Look
at
the
of
the
− C
H
3
a
of
branched
carbon
carbon
longest
is
1
to
the
propyl,
stem
− C
H
4
chain
in
+
-yl
7
atoms
atoms
chain
2n
suffix
alkane
and
this
contains
is
e.g.
butyl.
9
is:
name
chain.
six
name,
In
the
the
carbon
compound
example
atoms,
so
in
the
named
after
hexane.
is
the
side
chain(s)
methyl-.
position
longest
So
of
carbon
and
the
the
name
alkyl
chain
it/them.
compound
so
side
that
is
a
chain.
the
In
this
example
the
methylhexane.
Number
side
chain
is
from
given
one
end
the
12.3.3
lowest
group
114
chain
number
ethyl,
5
naming
longest
12.3.3
is
the
a
H
of
Figure
for
adding
in
H
−
H
H
−
H
C
−
−
−
H
−
the
Figure
−
−
H
−
C
−
−
−
−
−
C
−
H
H
H
−
the
after
−
H
H
2
procedure
Find
by
chain
H
n

carbon
groups
number
comes
possible.
off
from
In
the
Figures
third
12.3.3
carbon
and
atom.
12.3.4
the
methyl

Name
the
compound
by
including
the
position
of
the
alkyl
group
H
a
number
followed
by
a
hyphen.
In
this
case
the
compound
−
as
is
−
H
examples
of
organic
compounds
H
H
5
H
H
−
more
4
−
C
−
some
3
−
C
−
shows
−
C
−
−
−
12.3.5
−
C
2
H
Figure
−
C
1
H
−
−
C
H
−
−
examples
H
−
−
−
H
More
H
−
H
H
−
C
3-methylhexane.
6
H
H
for
Correct
numbering
naming.
H
−
−
H
CH
2
H
3
−
−
C
Incorrect
CH
−
−
CH
C
−
CH
3
CH
=
−
CH
−
−
CH
−
CH
2
−
3
−
CH
Figure
3
3
2
H
−
H
−
H
C
−
H
H
B
4
H
−
C
−
Compound
H
−
C
−
−
A
−
C
5
−
Compound
−
C
6
H
H
−
CH
2
3
−
C
H
H
3
−
−
CH
CH
−
CH
2
−
−
−
CH
−
CH
3
−
−
−
CH
2
−
CH
−
CH
3
3
−
−
−
CH
−
CH
CH
3
−
CH
1
H
H
numbering
12.3.4
CH
2
3
CH
2
3
CH
3
Compound
C
Compound
D
EXAM
Figure
TIP
12.3.5
When
draw
ing
struct
ure
Compound
A
is
2,3-dimethylbutane.
The
longest
chain
has
of
four
hydr
ocarbo
ns,
carbon
atoms
(butane).
T
wo
methyl
groups
come
off
at
carbon
and
3.
Note
the
comma
between
the
2
and
the
the
atoms
atom
B
counting
Compound
double
of
the
from
is
3-ethylhexane.
(hexane).
C
ethyl
from
is
bond
An
the
double-bonded
the
right.
So
the
longest
comes
off
chain
from
has
the
six
carbon
third
alkenes,
the
number
The
The
carbon
name
chain
lowest
has
five
number
atoms
is
position
between
is
carbon
that
arrived
pent-2-ene
can
at
and
atoms
be
when
not
and
given
you
to
D
is
a
count
pent-3-ene.
KEY
of
the
double
bond
is
shown
by
POINTS
When
Structural
the
stem
and
the
2,2-dimethylpentane.
group,
each
is
numbered
even
molecular
When
there
is
more
than
when
it
comes
off
at
the
but
displayed
formulae.
In
chain
isomerism,
the
same
of
the
carbon
atom.
many
different
displayed
formulae?
of
is
3
The
the
one
skeleton
How
have
formula
suffix.
structure
carbon
isomers
writing
2
alkyl
of
draw
n
one
different
Compound
is
ho riz
onta
lly.
same
the
atom
s
carbon
1
naming
sure
chain
left.
pent-2-ene.
(pentene).
The
group
longe
st
3.
carbon
Compound
mak
e
atoms
that
2
the
bran
ched
molecular
formula
pentane
C
H
5
skeleton
in
different
as
many
isomers
different
with
the
ways
as
molecular
.
By
arranging
the
carbon
In
is
different.
position
isomerism,
position
of
the
group
different.
the
functional
12
possible,
formula
we
C
can
H
5
draw
(Figure
all
the
is
12.3.6).
4
12
Alkyl
groups
general
have
formula
the
C
H
n
5
Isomers
are
2n
named
+
1
taking
CH
−
CH
−
CH
3
−
2
−
CH
−
CH
2
2
CH
−
CH
3
3
CH
into
consideration
−
CH
C
3
−
−
CH
2
CH
−
CH
3
number
3
the
longest
position
2-methylbutane
12.3.6
The
compound
with
the
molecular
carbon
formula
chain
atoms
and
and
in
nature
the
of
the
2,2-dimethylpropane
alkyl
Figure
of
3
CH
pentane
the
3
−
−
CH
3
C
H
5
has
three
side
chains.
isomers.
12
115
12.4
Sources
of
hydrocarbons
Natural
LEARNING
gas
Petroleum
At
the
end
of
this
topic
be
able
(crude
identify
natural
petroleum
of
as
gas
is
and
natural
the
main
fractions
the
and
are
of
obtained
fractional
and
is
rock
also
It
natural
found
below
also
butane.
unbranched,
uses
of
methane.
propane
sources
hydrocarbons
list
layers
mainly
gas

oil)
that
gas
are
trapped
natural
between
sources
of
impervious
(non-
to:
porous)

petroleum
you
hydrocarbons
should
and
OUTCOMES
the
Earth’s
contains
Petroleum
branched
and
ring
a
is
surface.
smaller
a
thick
Natural
amount
liquid
hydrocarbons
in
of
gas
ethane,
mixture
which
of
some
natural
dissolved.
some
from
distillation
of
Fractional
distillation
of
petroleum
petroleum
Petroleum

describe
the
thermal
the
catalytic
cracking
of
refining
hydrocarbon
mixture
removal
into
of
smaller
impurities,
groups
of
then
separation
hydrocarbons
of
called
alkanes.
fractions.
a
limited
(Figure
Each
range
Fractional
under
involves
and
fraction
of
molar
distillation
is
consists
masses
carried
of
a
and
out
mixture
number
using
a
of
of
hydrocarbons
carbon
having
atoms.
fractionating
column
12.4.1).
40 °C
Gas
for
heating,

The
petroleum

There
is
heated
to
400 ºC.
Fractionating
cooking
and
column
making
chemicals
the
is
a
gradient
bottom
than
of
at
temperature
the
in
the
column,
which
is
hotter
at
top.
40–100 °C

Gasoline
fuel
for
Hydrocarbons
with
very
high
molar
mass
do
not
vaporise
and
are
–
cars
(petrol)
tapped
off
at
the
masses
undergo
bottom
of
fractional
the
column.
distillation
Those
(see
with
lower
molar
2.5).
80–170 °C
Naphtha
making

–
As
distillation
proceeds,
the
more
volatile
hydrocarbons
in
the
chemicals,
petroleum,
especially
which
have
a
lower
molar
mass
and
lower
boiling
point,
plastics
move
further
up
the
column.
170–250 °C
Kerosene
(paraffin)
–

fuel
and
for
jet
Less
volatile
hydrocarbons,
with
a
higher
molar
mass
and
higher
aircraft
boiling
heating
point,
do
not
move
as
far
up
the
column.
250–350 °C

Diesel
Heated
oil
(light
fuel
for
and
tractors
gas-oil)
As
the
hydrocarbon
lower
boiling
boiling
crude
vapours
move
up
the
column,
the
ones
with
–
lorries
points
move
further
ahead
of
those
with
higher
points.
350–500 °C
oil
Fuel
fuel
oil
for
(heavy
power
gas-oil)
–

At
particular
points
hydrocarbons
ships
and
home
with
a
the
column,
particular
the
range
vapour
of
molar
containing
masses
and
boiling
heating
points
Lubricating
oil
condenses.
These
liquid
mixtures
of
hydrocarbons
(fractions)
–
are
lubricants,
and
in
stations,
removed
from
the
column.
waxes
polishes

The
petroleum
gases
which
contain
hydrocarbons
with
1–4
carbon
Residue
atoms
Bitumen
road
–
12.4.1
Fractional
and
These
are
distillation
116
at
the
temperatures
removed
at
the
top
of
12.4.1
shows
some
uses
of
the
within
the
column.
column.
different
of
fractional
petroleum
condense
roofs
T
able
Figure
not
making
sur faces
sealing
do
distillation
of
petroleum.
fractions
obtained
by
the
T
able
12.4.1
Uses
Fraction
of
petroleum
Number
atoms
of
in
fractions
carbon
Use
of
Gas
for
EXAM
fraction
Y
ou
Refinery
gas
TIP
fraction
1–4
heating
and
do
no t
remem
ber
manufacture
of
4–10
Gasoline
for
car
and
and
Naphtha
for
making
atom
s
need
Fuel
for
jet
aircraft
and
Fuel
oil
oil
16–20
Fuel
for
cars,
20–25
Fuel
for
power
and
home
Lubricating
lorries
in
of
to
but
each
you
know
do
some
uses
heating
of
Diesel
rang
e
chemicals
fractio
n,
10–16
boiling
the
naphtha
Kerosene
to
fuel
carbon
(petrol)
the
petrochemicals
points
Gasoline
have
cooking,
and
stations,
buses
at
least
three
of
the
fractio
ns.
ships
heating
more
than
25
Lubricants,
more
than
30
Road
waxes
and
polishes
oil
Bitumen
surfacing
and
roofing
Cracking
Some
fractions
from
the
distillation
of
petroleum
are
more
useful
KEY
than
by
others.
the
We
use
fractional
more
gasoline
distillation
of
(petrol)
petroleum.
than
We
can
use
a
be
process
called
1
cracking
to
convert
fractions
containing
larger
POINTS
supplied
Natural
with
molecules,
which
are
less
useful,
into
smaller,
more
Kerosene
and
diesel
oil
are
often
cracked
to
more
gasoline
more
alkenes,
chemicals

small
amounts
propane
of
and
butane.
Petroleum
is
a
natural
which
such
as
are
useful
polymers
materials
(see
for
making
other
hydrocarbons
source
from
14.2)
1
atoms
to
in
over
their
containing
30
carbon
molecules.
hydrogen.
3
Cracking
make
is
the
thermal
shorter-chained
decomposition
alkanes
and
of
longer-chained
alkanes
The
of
to
fractional
petroleum
produces
alkenes.
In
thermal
at
a
alkanes
cracking,
pressure
and
at
alkenes
C
H
8
fractions
containing
temperatures
is
formed.
(g)
→
For
C
18
H
5
octane
uses.
above
larger
700 ºC.
alkanes
A
are
mixture
a
smaller
example:
(g)
+
C
12
H
3
pentane
fraction
of
heated
of
A
is
a
mixture
hydrocarbons
limited
range
masses
and
carbon
atoms.
C
H
12
(g)
→
26
H
8
dodecane
cracking
C
(g)
+
a
5
Cracking
is
the
thermal
hydrocarbon
molecules
form
hydrocarbon
relatively
high
proportion
of
smaller
cracking
through
molecules
alkenes.
a
the
mixture
gaseous
of
kerosene
silicon( IV)
oxide
or
diesel
and
oil
fractions
Thermal
and
alkenes.
cracking
The
oxide
mixture
acts
as
a
catalyst.
aluminium
Catalytic
oxide
temperature
uses
relatively
high
proportion
of
hydrocarbons
for
high
at
Catalytic
cracking
uses
a
cracking
temperature
a
and
pressure.
are
7
400–500 ºC.
use
of
400–500 ºC
in
and
gasoline
to
cracking
catalytic
produces
larger
butene
high
passed
of
(g)
8
6
Catalytic
of
(g)
H
4
octane
produces
C
molar
6
propene
18
having
of
number
decomposition
Thermal
oil)
with
cracking
4
high
distillation
(crude
fractions
particular
Thermal
In
methane
(petrol)
of

mainly
make:
2

is
useful
ethane,
hydrocarbons.
gas
hydrocarbon
a
catalyst.
(petrol).
117
13
Reactions
13.1
the
end
Alkanes:
an
of
this
topic
be
able
Alkanes
saturated
alkanes
the
in
are
H
.
2n
+
The
reactions
terms
of
in
Figure
burning
H
H
general
formula
alkanes
H
are
H
H
H
H
−
−
−
−
−
−
−
−
−
C
H
H
C
C
C
H
H
−
−
C
C
C
C
−
H
−
H
H
−
−
−
H
−
−
H
H
−
H
H
(CH
)
ethane
(C
H
2
)
propane
(C
6
H
3
)
butane
(C
8
H
4
)
10
reactions
properties
to
−
−
the
C
−
H
H
4
alkanes
H
−
mainly
methane
relate
H
−
−
being
C
−
−
of
−
−
as
substitution
their
uses
Figure
of
as
13.1.1
fuels
The
alkanes
are
colourless
compounds
showing
a
gradual
change
in
solvents
physical
describe
of
the
unbranched
H
H
−
−
reactions
−
the
−
H

with
four
13.1.1.
−
describe
and
first
halogenation
alkanes

the
of
H

of
2
H
and
hydrocarbons
structures
to:
shown
describe
introduction
you
n

compounds
OUTCOMES
C
should
carbon
Alkanes
LEARNING
At
of
the
biogas
production
from
chain
the
decomposition
of
way
manure.
properties
increases.
as
the
increases
series
more
number
(Figure
are
carbon
gases
atoms
than
as
For
number
of
at
r.t.p.
The
at
first
carbon
in
are
atoms
points
the
four
with
r.t.p.
atoms
of
boiling
atoms
Alkanes
liquids
carbon
the
carbon
13.1.2).
are
17
the
example,
of
unbranched
solids
with
at
the
unbranched
members
Alkanes
in
increase
the
unbranched
in
a
regular
chain
homologous
chains
of
5–17
unbranched
chains
of
r.t.p.
)C°(
100
tniop
Combustion
50
gnilioB
0
In
the
presence
alkanes
–50
burn
(smoky).
In
of
of
with
the
alkanes
excess
a
oxygen
clear
presence
blue
of
or
air
flame,
excess
(which
which
air
,
we
contains
does
say
not
that
21%
oxygen),
appear
the
alkane
sooty
undergoes
–100
complete
–150
These
are
2
3
Number
4
5
of
carbon
in
chain
13.1.2
The
are
oxidised
boiling
points
of
alkanes
2C
the
vary
H
oxygen
(or
very
in
heaters
If
or
The
an
colourless
poisonous.
gas
is
and
gas
the
air
boilers
that
is
flame
sooty
formed
carbon
and
this
carbon
Examples
water
.
and
are:
2O
(g)
→
CO
13O
(g)
+
2H
2
(g)
→
O(l)
2
8CO
(g)
+
10H
2
O(l)
2
not
in
excess,
kill
products
water.
(g)
Some
+
7O
8
of
alkanes
undergo
incomplete
incomplete
carbon
(g)
→
may
combustion
also
6CO(g)
remain
+
8H
2
produced
of
from
the
are
carbon
unreacted.
O(l)
2
incomplete
unreacted
combustion
carbon
particles
can
be
yellow
and
present.
holes
of
alkanes
with
halogens
is
you.
Alkanes
halogen
light
a
a
do
not
with
react
an
reaction
chlorine
called
118
the
and
become
monoxide
can
+
+
is
The
H
because
Reaction
blocked,
which
reduced.
2
air)
2C
KNOW?
monoxide
odourless,
in
is
2
(g)
3
Carbon
oxygen
dioxide
way.
monoxide
YOU
(g)
10
combustion.
DID
reactions,
carbon
in
If
regular
the
are
atoms
4
a
and
4
unbranched
products
6
CH
Figure
The
oxidation–reduction
hydrogen
1
combustion.
atom
with
alkane
takes
in
the
place.
replaces
halogenation
halogens
a
in
the
presence
When
dark.
of
chlorine
hydrogen
atom
If
we
sunlight
reacts
in
the
or
mix
a
gaseous
ultraviolet
with
(uv)
methane,
methane.
This
is
H
H
C
−
+
H
−
Cl
−
−
H
−
uv
light
Cl
−
H
EXAM
−
C
+
Cl
HCl
−
−
H
TIP
When
balanc
ing
H
equa
tions
methane
A
reaction
replaces
chloromethane
such
as
another,
this,
is
in
called
which
a
one
atom
substitution
or
group
of
organi
c
atoms
the
presence
of
excess
chlorine,
the
hydrogen
atoms
the
one
by
one
until
there
are
none
hydr
ogen
.
CH
Cl(g)
+
Cl
3
of
of
first
then
Leav
e
the
left.
until
uv
carbon
,
are
balanc
ing
substituted
react
ions
compo
unds
,
balanc
e
reaction.
the
In
fo r
combu
stion
the
oxyg
en
last.
light
(g)
CH
2
Cl
2
(l)
+
HCl(g)
2
dichloromethane
uv
CH
Cl
2
(l)
+
Cl
2
light
(g)
CHCl
2
(l)
+
HCl(g)
3
DID
YOU
KNOW?
trichloromethane
The
uv
CHCl
(l)
+
Cl
3
compounds
formed
when
light
(g)
CCl
2
(l)
+
halogens
HCl(g)
react
with
alkanes
4
are
called
haloalkanes.
CHCl
tetrachloromethane
Apart
from
combustion,
the
reactions
of
alkanes
are
trichloromethane.
to
of
Alkanes
energy
and
gas)
are
good
is
are
used
variety
of
fuels
because
combustion.
butane
as
used
a
fuels
fuel
(see
the
upper
alkanes
on
e.g.
alkanes
in
are
marking
as
in
they
Gaseous
fuels
cars.
in
burn
alkanes
bottled
Mixtures
cleanly
such
gas.
of
and
release
a
lot
methane,
propane
LPG
(liquefied
petroleum
alkanes
are
used
for
KEY
a
1
as
solvents
for
a
variety
of
organic
Alkanes
2
or
household
waste
is
left
for
a
time
in
the
absence
material
and
fungi
that
decomposition.
and
methane,
biogas
hydrogen
can
from
it
contains
begins
to
decompose
(break
carbon
water.
monoxide
are
and
formed
during
combustion
A
substitution
respire
in
the
absence
of
air
are
They
produce
gases
such
as
be
used
animal
sulfide.
as
and
a
The
fuel
plant
gaseous
called
waste
mixture,
biogas.
for
or
which
is
in
which
of
use
produce
the
4
electricity.
Alkanes
undergo
6
or
hydrogen
more
as
Biogas
plant
waste
into
methane
the
the
by
which
alkane
are
halogen
are
used
one
atoms.
as
fuels
solvents.
is
a
fuel
breakdown
organic
absence
and
of
in
Alkanes
other
animal
substitution
halogens
in
the
turn
with
(halogenation)
and
digesters
or
replaced
another.
reactions
5
Biogas
atom
is
carbon
replaced
13.1.3
one
atoms
largely
farmers
to
is
responsible
methane,
Some
heating
reaction
down).
atoms
Figure
complete
form
alkanes.
by
dioxide
to
incomplete
group
this
undergo
and
Carbon
one
for
the
of
3
organic
Bacteria
in
production
manure
the
linked
ozone
substances,
pens.
of
air
,
been
of
POINTS
combustion
12.4).
used
have
atmosphere.
the
When
banned
of
as
liquid
they
carbon
Biogas
now
reduction
dioxide
Liquid
are
reactions.
because
Uses
Many
generally
haloalkanes
substitution
is
3
called
of
formed
of
by
manure
waste
in
or
the
air.
gas.
119
13.2
Alkenes
Structure
Alkenes
At
the
end
of
this
topic
H
n

be
able
describe
alkenes
the
are
unsaturated
hydrocarbons
.
The
structures
of
some
alkenes
reactions
13.2.1.
−
C
−
H
C
=
−
C
C
C
−
H
H
−
H
H
acidified
H
manganate( VII)
−
−
−
C
−
−
=
−
C
H
H
−
C
−
=
C
H
H
H
−
with
potassium
formula
Figure
H
−
halogens,
H
−
H
H
reaction
general
in
of
burning,
−
with
of
−
terms
−
reaction
the
shown
2n
−
in
are
to:
H
alkenes
with
you
C
should
of
OUTCOMES
−
LEARNING
H
H
and
ethene
(C
H
2
)
propene
(C
4
H
3
)
but-1-ene
(C
6
H
4
)
8
hydrogen

describe
the
reactions
of
Figure
alkenes
as
mainly
13.2.1
addition
reactions

describe
tests
between
to
distinguish
alkanes
and
Combustion
relate
the
alkenes
properties
to
starting
their
uses
materials
of
as
complete
dioxide
For
and
synthesis
of
the
H
4
polymers.
soo tin
ess
as
a
of
positiv
e
distin
guis
h
from
the
use
test
a
in
oxygen
a
large
produces
amount
usin
g
or
It
energy.
(g)
→
4CO
a
higher
burn
in
carbon
can
use
the
alkanes
ratio
air,
and
particles
colour
(g)
+
4H
2
in
and
carbon
unreacted
make
of
of
addition
the
the
alkenes.

alkanes
burn
with
a
clean

alkenes
burn
with
a
yellow
to
to
as
a
rough
burnt
than
dioxide
particles
yellow
When
blue
hydrogen
carbon
carbon
flame
flame
O(l)
2
and
in
are
for
water,
also
sooty
guide
alkanes.
and
formed.
(blackish).
We
distinguishing
air:
flame
sooty
flame.
Addition
reactions
of
alkenes
of
reactions
guid
e.
addition
reaction,
a
of
alkenes
reactant
molecules
single
are
and
no
product
addition
other
is
formed
reactions.
product
is
from
two
(or
In
an
more)
made.
the
brom
ine
Reaction
with
halogens
po tass
ium
Alkenes
).
fo r
react
with
halogens
to
form
dihaloalkanes.
The
halogen
adds
See
across
o ppos
ite
the
only
use
man
gana
te(VII
de tails
.
the
bromine
double
reacts
bond
with
and
ethene
no
to
other
form
product
is
formed.
−
Br
H
−
C
−
C
−
H
−
−
−
H
Br
−
H
+
Br
−
C
−
=
−
−
C
For
1,2-dibromoethane:
Br
H
H
H
ethene
120
carbon
of
to
satu
rated
roug
h
shou
ld
water
6O
monoxide
The
Most
Y
ou
alkene
produces
unsa
turated
compo
unds
.
gives
an
the
flam
e
test
+
have
between
no t
of
reaction
2
they
carbon
TIP
(g)
8
Alkenes
When
shou
ld
The
example:
C
including
Y
ou
combustion
water.
for
synthesis
EXAM
alkenes
alkenes
The

of
bromine
H
1,2-dibromoethane
example,
Bromine
So
is
when
gets
red-brown
we
add
a
decolourised.
in
colour
drop
This
of
but
1,2-dibromoethane
bromine
reaction
is
to
the
excess
basis
alkene,
of
the
is
the
colourless.
EXAM
bromine
bromine
water
TIP
test
When
for
distinguishing
used
and
to
between
distinguish
alkanes
C − C
between
and
alkenes.
bonds
in
It
is
therefore
saturated
brom
ine
compounds
do
C = C
bonds
in
unsaturated
describ
ing
also
compounds.
no t
water
write
brom
ine
Liquid
bromine
is
too
hazardous
for
use
in
schools.
So
we
use
instead.
This
is
a
solution
of
bromine
in
water
.
water
Bromine
water
T
he
when
concentrated
and
orange
when
‘the
goes
wo rd
‘clear
’
is
chem
istry
red-brown
test
that
bromine
clear
’.
water
the
dilute.
does
no t
in
mean
co lou
rless
.

When
bromine
occurs.

When
The
bromine
bromine
reaction.
water
The
is
added
water
water
is
bromine
to
an
remains
added
water
to
is
alkane
in
the
red-brown
an
alkene
in
decolourised
dark
(or
no
reaction
orange).
the
dark
(goes
there
is
a
colourless).
DID
Reaction
with
addition
of
hydrogen
hydrogenation
passed
through
catalyst.
For
to
reaction.
the
an
alkene
Alkanes
alkene
at
are
150 ºC,
is
an
example
formed.
in
the
of
in
a
Hydrogen
presence
of
gas
a
bromine
the
When
Ni,
3
+
of
test
minimise
a
reaction
a
CH
2
CH
3
propene
products
CH
2
is
to
propane
reacts
mixture
formed.
In
of
are
used
to
addition
1,2-dibromoethane,
CH
BrCH
2
reactions
occurring.
water
3
compound
Hydrogenation
done
light-catalysed
bromine
ethene
is
the
150 ºC
H
2
water
to
substitution
nickel
example:
CH = CH
dark
possibility
is
with
CH
KNOW?
hydrogen
The
The
YOU
change
vegetable
oils
the
OH
is
also
2
into
formed.
The
OH
arises
from
the
margarine.
water
Hydration
The
of
addition
in
the
of
steam
industrial
to
alkenes
is
preparation
also
of
an
addition
alcohols
(see
of
reaction.
It
purple
alkenes
solution
decolourised
which
as
a
by
with
to
of
cold
alkenes.
potassium
test
potassium
POINTS
manganate( VII)
The
acidified
This
is
an
manganate( VII)
distinguish
alkenes
potassium
manganate( VII)
oxidation–reduction
is
the
from
oxidising
agent.
Alkanes
are
unaffected
by
cold
can
be
in
2
used
Alkenes
3
decolourise
manganate.
The
[O]
a
solution
in
the
of
cold
equation
the
potassium
acidified
represents
potassium
the
The
= CH
2
+
[O]
+
H
2
O
→
HO–CH
2
–CH
2
ethene
oxygen
This
be
Alkenes
to

Alkenes
the
plastics,
are
but
bromine
alkanes
do
ethane-1,2-diol
Alkenes
but
important
especially
e.g.
alkenes
reactions.
decolourise
dark
decolourise
chemicals
in
chemical
synthesis.
They
are
used
6
ethanol
(see
7
13.3)
do
poly(ethene)
from
ethene,
poly(propene)
from
not.
Alkenes
react
to
alkanes.
form
Alkenes
acidified
manganate( VII)
alkanes
are
with
used
manufacture

of
addition
not.
–OH
make:
alcohols,
the
2
alkenes
are
causes
sooty.
reactions
potassium
of
in
remains
arising
5
Uses
burn
carbon
manganate( VII).
in
CH
to
mainly
4
from
of
dioxide
potassium
manganate(VII).

alkenes
some
unburnt.
acidified
carbon
water.
When
air
alkanes.
dilute
combustion
forms
is
reaction
It
complete
alkenes
flame

solution.
is
and
A
the
13.3).
1
Oxidation
in
alkenes
KEY
used
present
hydrogen
to
alcohols
and
propene
plastics.
and
poly(chloroethene)
(PVC)
from
chloroethene,
= CHCl.
CH
2
121
13.3
Alcohols
Structure
LEARNING
Alcohols
At
the
end
of
alcohols
OUTCOMES
of
this
topic
contain
− OH
the
functional
have
the
general
formula
C
H
n
should
be
able
relate
the
properties
of
three
H
−
−
C
O
−
H
−
H
C
hydration
produce

the
in
reactions
terms
sodium,
the
of
YOU
in
the
practice
of
reaction
principles
for
organic
reactions
absence
not
reactions,
H
H
ethanol
Some
physical
H
H
propan-1-ol
properties
Alcohols
evaporate
with
same
of
the
much
number
of
alcohols
to
it
is
put
less
easily
Volatility
the
less
easily
the
− OH
of
state
especially
is

than
the
group
than
the
corresponding
atoms.
We
say
symbols
also
a
are
because
organic
when
stronger
an
than
solvent.
the
the
boiling
boiling
point
to
point.
are
alkanes
less
of
a
compound
alkanes
be
polar
Alcohols
because
(see
the
the
get
of
water
.
5.6).
in
and
of
is
water
alcohols
by
liquids
–
the
evaporate
presence
There
are
the
alkane
as
the
are
by
the
than
or
is
in
of
and
a
of
stronger
soluble
the
than
the
atoms.
There
and
of
in
r
.t.p.
soluble
water
length
at
carbon
alcohols.
alcohol
very
those
solids
more
number
present
between
ethanol
manufactured
are
same
corresponding
soluble
molecules
Alcohols
the
group
attraction
the
less
alcohols
with
− OH
Methanol
are
in
alkanes
polar
force
So
alcohol
water
is
a
in
This
much
The
carbon
chain
water
.
hydration
reaction
of
steam
with
a
This
that
gaseous
The
cataly
st)
react
ions

a
catalyst

a
temperature

a
pressure
of
−
rally
reaction.
because
it
The
reaction
involves
the
is
also
addition
called
of
a
water
conditions
for
the
reaction
are:
writt
concentrated
of
phosphoric
acid
330 ºC
60–70
atmospheres.
en
H
phosphoric
acid
H
−
the
C
=
C
H
O
H
330 °C, 60 –70 atm
−
C
−
H
H
ethene
Figure
C
13.3.2
H
ethanol
The
addition
reaction
between
ethene
and
steam
−
−
2
−
H
+
−
−
in
−
arrow
of
T
hese
H
equa
tion.
13.3.2).
−
of
learn
.
the
addition
you
pressu
re
organi
c
gene
an
cond
ition
s
nam
e
you
is
reaction
is
molecules
molecules.
their
H
the
(tem
peratu
re,
abov
e
them
between
insoluble
between
alcohols
(Figure
that
they
TIP
impo
rtant
the
to
higher
corresponding
alkane.
corresponding
hydration
and
related
the
causes
attraction
Alkanes
alkene.
is
is
volatility,
corresponding
take
water
.
of
Alcohols
know
carbon
the
general
involving
reactant
EXAM
of
ethanol.
Manufacture
122
−
13.3.1
increases.
are
O
dehydration
test
this,
equations
fo r
−
KNOW?
organic
Because
It
C
of
force
in
−
C
of
lower
place
H
H
volatile.
breathalyser
Many
−
oxidation
describe
DID
C
alcohols

and
−
H
−
with
H
−
ethanol
−
−
describe
O
−
the
to
Figure

−
C
volatility
methanol
alkenes
−
−
in
H
−
solubility
H
H
−
of
−
describe
and
the
1
H
H
H

group)
shows
−
terms
and
(hydroxyl
13.3.1
of
functional
−
water
+
−
in
their
−
group
to
2n
Figure
alcohols.
H
alcohols
OH.
to:
structures

group
you
O
−
H
Reaction
of
alcohols
Combustion
Many
alcohols
dioxide
and
burn
water
combustion
of
CH
in
are
excess
air
formed.
with
The
a
clean
equation
blue
flame.
below
Carbon
represents
Water
out
the
ethanol.
CH
3
OH
+
3O
2
→
2CO
2
+
3H
2
O
2
Water
Reaction
Ethanol
The
with
reacts
reaction
with
is
sodium
similar
to
to
that
form
sodium
between
ethoxide
sodium
and
and
hydrogen.
water.
Ethanol
2CH
in
sodium
CH
3
OH
+
2Na
→
2CH
2
CH
3
ONa
+
+
H
2
2
acidified
ethanol
sodium
ethoxide
potassium
manganate(VII)
Dehydration
When
ethanol
is
mixed
with
concentrated
sulfuric
acid
and
heated
Heat
to
170 ºC,
ethene
is
formed.
This
reaction
is
called
a
dehydration
Figure
reaction
because
water
is
13.3.3
Reflux
apparatus
preparing
conc.
H
SO
2
CH
CH
3
,
170 ºC
from
OH
= CH
CH
2
concentrated
2
+
H
2
acid
ethanol
O
2
KEY
ethene
sulfuric
ethanoic
4
ethanol
The
for
removed.
acid
acts
as
a
dehydrating
agent.
1
POINTS
Alcohols
and
are
more
less
volatile
soluble
in
water
Oxidation
than
alkanes
number
Alcohols
agent
are
oxidised
potassium
to
alkanoic
acids
manganate( VII).
An
by
heating
alternative
with
the
oxidising
dichromate( VI).
In
both
cases
a
few
drops
of
acid
is
are
needed
done
under
for
the
reflux.
best
This
conditions
involves
for
oxidation.
heating
the
Ethanol
apparatus
shown
in
Figure
13.3.3.
Having
the
is
manufactured
condenser
hydration
position
prevents
the
volatile
alcohol
from
in
catalyst
oxidation
of
ethanol
to
ethanoic
acid
using
of
phosphoric
K
Cr
2
O
2
,
can
be
represented
by
acid.
Alcohols
undergo
complete
to
carbon
escaping.
and
water.
potassium
4
dichromate(VI),
by
using
the
dioxide
The
ethene
in
combustion
upright
of
The
reactants
3
the
same
atoms.
concentrated
a
heating
carbon
is
the
sulfuric
the
oxidising
agent
2
potassium
of
with
the
Ethanol
reacts
to
sodium
with
sodium
equation:
7
form
ethoxide
+
H
/
K
Cr
2
CH
CH
3
OH
+
O
2
7
and
2[O]
CH
2
COOH
+
H
3
5
In
this
reaction,
the
orange
dichromate( VI)
ions
are
converted
Cr
ions
by
the
reducing
agent,
Ethanol
is
heating
with
breathalyser
6
test
acid.
Ethanol
is
ethanoic
Acidified
potassium
dichromate( VI)
was
used
in
early
breathalysers
the
alcohol
content
of
a
driver’s
breath.
The
driver
blows
into
oxidised
acid
by
to
refluxing
to
with
test
by
concentrated
ethanol.
sulfuric
The
dehydrated
to
3+
green
hydrogen.
O
2
acidified
potassium
a
manganate(VII).
bag
containing
acidified
potassium
dichromate( VI),
which
is
orange
in
7
colour.
If
the
driver’s
breath
contains
ethanol
vapour,
the
dichromate
degree
to
to
will
start
which
estimate
the
the
to
turn
green
potassium
approximate
as
Cr
Early
by
ions
dichromate
concentration
are
turns
of
formed.
green
alcohol
observing
be
the
used
breath.
change
breathalysers
use
electronic
methods
for
detecting
the
when
potassium
reduced
Modern
worked
colour
The
can
in
breathalysers
potassium
3+
acidified
dichromate
by
ethanol
is
vapour.
ethanol
concentration.
123
13.4
Fermentation
The
LEARNING
fermentation
Bacteria
At
the
end
of
this
topic
be
and
able
in
yeasts
describe
process
the
by
produced
compare
which
from
ethanol
the
by
energy.
is
carbohydrates
manufacture
fermentation
is
the
microorganisms
fermentation
Most
commonly
which
especially
in
catalyse
plant
fermentation
materials.
of
organic
effervescence
vegetable
used
starch.
breakdown
with
material
materials
Fermentation
are
is
materials
(bubbles)
can
be
to
make
such
by
the
fermented
carbohydrates
used
and
release
but
as
alcoholic
the
of
heat
most
glucose,
drinks.
sucrose
The
of
main
ethanol
enzymes
materials,
to:
and

produce
organic
Fermentation

carbohydrates
you
reactions
should
of
OUTCOMES
alcohol
in
these
drinks
is
ethanol.
The
overall
reaction
for
the
and
fermentation
of
glucose
is:
hydration

describe
the
process
enzymes
of
C
H
6
making
in
yeast
O
12
2C
6
glucose

H
2
OH
+
2CO
5
2
wine
describe
the
manufacture
ethanol
carbon
dioxide
of
The
conditions
needed
for
fermentation
are
the
following:
rum.

Temperatures
temperature
reactions
enzymes
Air
lock
(CO
can

escape
of
get
back
Fermentation
liquor
(yeast,
plant

Figure
13.4.1
Simple
of
may
grow
that
have
Reaction
pH
material,
Too
15 ºC
the
high
a
rate
and
of
35 ºC.
the
Too
low
a
enzyme-catalysed
temperature
will
denature
the
10.4).
are
The
yeasts
anaerobic.
that
This
are
responsible
means
that
they
for
alcoholic
respire
oxygen.
and
If
spoil
oxygen
the
is
allowed
into
the
in
alcoholic
fermentation
pH
near
mixture,
the
by
bacteria
producing
acids
vessel

sugar,
much.
about
down
in)
absence
Fermentation
slow
oxygen.
fermentation
cannot
between
but
2
air
too
(see
Absence
of
will
bad
taste.
mixture
values
Presence
it
a
would
of
with
slow
water.
Yeast
to
survive
and
Figure
13.4.1
shows
water)
a
value
down
is
a
the
rate
living
pH
of
7.
Too
reaction
organism,
so
acidic
of
the
water
or
alkaline
enzymes.
is
needed
for
grow.
the
apparatus
that
can
be
used
to
ferment
small
fermentation
quantities
apparatus
of
plant
material.
Winemaking
The
EXAM
the
Rem
embe
r
that
ferm
entatio
n
anae
robic
the
It
a
of
need
ed
that
fo r
are
in
error
oxyg
en
the

cause
the
many
the
yeast
putting
and
to
of
alcoholic
plants.
fermentation
grapes
content
Wine
(which
of
the
is
made
are
contain
grapes
is
from
naturally
natural
low,
grapes
present
on
yeast
on
particular
by:
their
surface).
strains
of
yeast
added.
the
crushed
allowing
grapes
fermentation
into
to
a
vat
take
(wooden
place
using
or
stainless
steel)
the
natural
sugars
in
grape.
is
ferm
entatio
n.

drawing

fermenting
sugar
124
that
surface
crushing
If
oxyg
en).
comm
on
sugg
est

is
(occur
s
absenc
e
is
yeasts
TIP
is
off
the
the
juice
juice
removed.
from
in
the
grape
wooden
When
the
or
wine
pulp.
stainless
is
ready,
steel
it
is
vats
so
bottled.
that
excess
The
manufacture
of
rum
DID
There
is
a
limit
to
the
concentration
of
alcohol
that
can
be
fermentation.
When
the
alcohol
content
rises
above
15%
winemaking,
it
kills
the
yeast.
Spirits
such
as
rum
are
made
by
added
fermentation
concentration.
Rum
sugar
refining

molasses
The
about

The
15%
yeast
variety
to

of
the
After
(see
is
–
a
they
is
Ageing
taste
still,
is
water
to
molasses
in
also
so
to
reaches
a
molasses,
carried
that
the
out
the
as
to
prevent
a
product
action,
which
tasting
acids.
follows:
sugar
content
is
which
and
give
carbon
dioxide.
particular
A
flavours
the
the
are
from
oak
in
is
an
gives
is
is
in
an
of
of
the
example
fractional
water
particular
of
put
in
flavours
materials
are
the
give
are
higher
cooler.
up
the
distillation.
barrels
rum
96%
to
a
which
mixture,
which
contains
the
that
vapour,
fractional
to
aroma
and
distillation.
fermentation
oak
distilled.
and
evaporate
rising
content
is
still.
alcohol
column
distillation
and
the
with
liquid
column
simple
The
the
alcoholic
a
flavours
filled
than
levels
in
and
condensation.
higher
with
or
example
content
This
fermentation
still
directly
column
for
the
pot
characteristic
higher
this
a
The
ethanol.
Figure
13.4.2
Rum
between
required,
particular
and
makes
it
the
quality
KEY
1
year
and
20
years,
depending
on
Ethanol
Fermentation
liquid
from
different
barrels
can
be
blended
to
brands
of
from
Making
ethanol
advantages
of
Fermentation
as
The
conditions
industrial
use
disadvantages
requires
still
by
fermentation
compared
distillation
contains
is
relatively
with
has
making
and
some
ethanol
35 ºC
Wine
and
the
ethanol
produced
and
Fermentation
batches.
absence
of
air
.
is
made
by
some
water.
The
ethanol
produced
fermentation
of
Rum
by
is
is
made
by
rate
of
reaction
is
slow.
For
hydration,
a
a
lot
of
very
enables
simple
relatively
The
fermented
liquor
from
is
distilled
by
simple
large
ethanol
method
and
tanks
and
to
made
be
uses
can
only
be
complex,
and
the
or
fractional
distillation
to
increase
made
catalyst
are
expensive.
ethanol
content.
Making
ethanol
resources.
temperature,
Hydration
uses
for
industrial
high
by
fermentation
has
non-renewable
some
(petroleum
the
continuously.
renewable
high
distillation
use
and
molasses.
fast.
needs
is
of
the
6
is
grapes.
pure.
the
Hydration
Fermentation
resources
15 ºC
by
rum
reaction
pressure
yeast,
by
5
fermentation,
Hydration
and
for
are
between
fermentation
of
dioxide
products.
rum.
4
hydration
glucose
ethene.
distillation

casks.
make
3
hydration
in
oak
fermentation
for
and
of
carbon
temperature

in
POINTS
fermentation
rate
aged
of
2
For
is
age.
ethanol

bitter-
of
produces

bacterial
makes
smoother.
After
rum
is
after
suitable
1

dioxide
grapes
mixture.
ethanol
occur,
applied
the
ethanol
in
diluted
in
is
This
area
reach.
distillate

process
added
place
heat
surface
vapours
This
alcohol
fermenting
fermentation,
giving
column
higher
still
the
by
with
is
the
take
still,
condenses
The
The
reactions
condensed.
large
is
yeast
of
either
pot
then
a
2.6).
ferments
other
compounds
In
made
diluted
and
48 hours
can
–
is
when
the
rum.
This
In
mixture
to
distilling
crushing
the
sulfur
by
often
volume,
KNOW?
produced
In
by
YOU
advantages
and
some
fractions).
disadvantages
with
making
it
compared
by
hydration.
125
13.5
Alkanoic
Structure
Alkanoic
At
the
end
of
this
topic
be
able
the
properties
in
terms
alkanoic
volatility
COOH.
2n
+
Figure
physical
of
of
acids
(carboxylic
acids)
(carboxylic
H
n
describe
acids
acid
group)
and
contain
have
the
− COOH
the
general
The
structures
of
three
alkanoic
acids
are
acids
C
−
−
C
−
−
=
=
O
−
C
H
O
H
acid
(HCOOH)
ethanoic
acid
(CH
COOH)
propanoic
acid
(C
3
and
fo rm
ulae
3
fo r
alka
noic
remem
ber
the
in
grou
p.
CH
physical
properties
of
alkanoic
acids
Alkanoic
acids
are
less
volatile
than
the
corresponding
alkanes
with
writi
ng
the
atom
COOH)
5
13.5.1
Some

coun
t
H
2
TIP
When
acids,
H
carbonates.
Figure
EXAM
−
H
H
metal
methanoic
hydroxides
O
−
H
H
with
oxides,
C
−
metal
−
−
−
metals,
acids
C
−
alkanoic
−
−
H
O
−
C
H
H
−
reactions
−
−
the
H
O
O
of
in
and
H
describe
shown
1
13.5.1.
solubility

functional
formula
to:
C

alkanoic
you
group
should
of
OUTCOMES
=
LEARNING
acids
For
CH
2
pro pa
noic
of
—CO
OH
COOH
2
acid
and
acid.
number
causes
attraction
is
no t

Alkanoic
with
the
them
force
than
of
acids
be
polar
alkanoic
So
more
polar
atoms.
(see
acid
alkanoic
soluble
of
between
corresponding
get
less
increases.
Methanoic
acids
in
acid
There
are
the
atoms.
alkane
water
and
is
of
a
− COOH
the
stronger
than
liquids
those
or
is
acid
a
much
the
ethanoic
of
of
are
r.t.p.
the
molecules
molecules.
length
acid
the
at
stronger
water
water
force
alkanes
because
and
and
as
is
in
solids
corresponding
This
There
alkanoic
the
soluble
5.6).
group.
the
presence
molecules
than
carbon
− COOH
The
their
very
The
carbon
soluble
water.
Reactions
Reaction
Aqueous
and
to
number
the
between
chain
are
attraction
alkanoic
in
acids
of
carbon
alkane.
same
presence
of
between
corresponding
exam
ple,
CH
buta
noic
group
to
carbon
the
same
of
with
alkanoic
metals
solutions
hydrogen
acids
of
gas.
alkanoic
For
2HCOOH(aq)
+
acids
react
with
metals
to
form
a
salt
example:
2Na(s)
→
2HCOONa(aq)
+
H
(g)
2
methanoic
2CH
acid
sodium
COOH(aq)
+
Mg(s)
→
(CH
3
are
alkanoic
called
acid
acids
are
weak
They
acids
are
(see
salts
of
7.2).
Mg(aq)
+
H
2
magnesium
alkanoates.
compounds.
126
COO)
3
ethanoic
The
methanoate
(g)
2
ethanoate
The
alkanoic
compounds
acids
and
formed
are
ionic
Reaction
with
metal
oxides
DID
Aqueous
solutions
of
alkanoic
acids
react
with
many
metal
YOU
oxides.
Many
A
salt
and
water
are
formed.
This
is
a
simple
acid–base
KNOW?
reaction.
alkanoic
acids
are
found
For
naturally
in
plants
and
animals.
example:
Methanoic
MgO(s)
+
2C
H
3
COOH(aq)
→
(C
7
H
3
butanoic
acid
COO)
7
Mg(aq)
+
H
2
magnesium
O(l)
sting
of
gives
the
Aqueous
with
hydroxides
solutions
water
are
of
alkanoic
formed.
This
is
acids
a
react
with
neutralisation
metal
hydroxides.
reaction.
For
A
+
CH
COOH(aq)
→
CH
3
The
weak
NH
alkali
(aq)
+
acid
ammonia
CH
3
reacts
COOH(aq)
in
a
→
CH
3
Aqueous
water
Na
CO
2
by
guavas
contain
+
2CH
3
of
alkanoic
dioxide
are
COOH(aq)
acids
H
fruits
O(l)
contain
with
on
presence
heating
formed.
to
For
vinegar
.
acids
fruits
present,
malic
acid
is
e.g.
and
citric
− COOH
the
e.g.
substances
acid.
aspirin
also
functional
and
vitamin
C.
(aq)
ethanoate
formed.
→
with
For
2CH
carbonates.
acid
A
salt,
example:
COONa(aq)
+
H
O(l)
+
CO
2
sodium
(g)
2
ethanoate
alcohols
Figure
the
to
some
contain
useful
group,
3
ethanoic
In
of
4
react
3
Reaction
+
the
taste
carbonates
carbon
(s)
COONH
3
solutions
and
the
acid
way:
ammonium
with
in
salt
ethanoate
similar
present
Ethanoic
example:
2
sodium
ammonia
Reaction
COONa(aq)
3
ethanoic
taste
caused
Some
NaOH(aq)
acidic
sharp
citrus
and
is
ants.
2
butanoate
The
Reaction
acid
fire
of
an
acid
produce
catalyst,
alkanoic
compounds
called
acids
react
esters.
with
Water
is
13.5.2
The
sting
contains
alcohols
of
fire
ants
methanoic
acid.
also
example:
+
H
CH
COOH
+
C
3
ethanoic
For
more
H
2
acid
details
OH
CH
5
about
COOC
3
ethanol
this
ethyl
reaction
see
H
2
+
H
5
O
2
EXAM
ethanoate
13.6.

T
he
TIPS
react
ions
alka
noic
KEY
POINTS
very
1
Alkanoic
acids
contain
the
− COOH
functional
Alkanoic
the
acids
are
corresponding
less
volatile
alkanes
and
with
more
the
soluble
same
in
number
water
of
than
of
carbon
and
the
acids
react
with
reactive
metals
to
form
metal
put
salts
in
me ta
l
hydrogen.
with
4
Alkanoic
acids
react
with
some
metal
oxides
to
form
and
Y
ou
water.
that
5
Alkanoic
acids
are
neutralised
by
alkalis
to
form
a
salt
a
and
Alkanoic
carbon
7
react
with
carbonates
to
form
a
salt,
if
the
ion
man
y
be
awar
e
chem
istry
water
.
water
and
acids
call
alka
noic
carbox
ylic
acids.
dioxide.
Alkanoic
catalyst
acids
an
be
charge
.
shou
ld
textb
ooks
6
of
the
shou
ld
s
2+
those
When
fo rm
ed,
bracke
ts
fo rm
are
fo rm
ulae
that
part
metal

salts
the
salts
RCOO
Alkanoic
acids.
remem
ber
atoms.
3
to
group.
writi
ng
2
acids
simila
r
minera
l
of
acids
to
react
form
with
alcohols
in
the
presence
of
an
acid
esters.
127
13.6
Esters
The
The
the
should
end
be
of
esters
of
this
able
topic
functional
group
in
esters
is:
you
=
At
structure
OUTCOMES
to:
the
in
functional
group
O
The

describe
the
formation
groups
from
alcohols
acids
describe
the
can
hydrolysis
are
required
be
either
of
shown
=
alkanoic
complete
in
ethyl
hydrogen
Figure
an
alkyl
−
CH
−
H
3
group.
7
C
Some
examples
of
O
CH
O
−
CH
3
3
ethanoate
methyl
H
flavourings
For
−
butanoate
O
C
is
used
−
CH
C
3
−
O
CH
O
−
CH
3
example,
methyl
in
CH
2
methanoate
propyl
CH
2
ethanoate
is
13.6.1
used
Esters
flavourings.
are
‘-oate’
prefix

C
H
3

named
part
of
comes
H
2
HCOOC
H
This
is
are
a
from
last
which
and
they
the
are
name
made.
of
the
So
the
alcohol
example:
ethyl
is
propyl
of
butanoate
methanoate.
esters
synthesised
acid
dilute
(Figure
For
acid
comes
7
called
sulfuric
is
the
name
5
Formation
Esters
after
the
fi rst.
COOC
7
3
by
warming
esterification.
is
used.
solution
13.6.2).
of
After
an
acid
warming,
sodium
The
An
typical
alcohol
catalyst,
the
carbonate,
sweet
of
the
an
usually
reaction
which
smell
with
alkanoic
mixture
reacts
ester
with
is
acid.
concentrated
is
poured
any
then
into
excess
made
acid
obvious.
Sulfuric
acid
Figure
13.6.3
The
due
smell
to
of
many
particular
fruits
types
is
of
esters.
Water
Sodium
carbonate
Ethanoic
acid
solution
+
ethanol
Heat
Figure
128
3
ethanoate
and
Figure
pear
or
C
=
in
flavourings
3-methylbutyl
in
diagram
−
used
methanoate
raspberry
the
KNOW?
perfumes.
ethyl
in
13.6.1.
O
and
shown
−
are
bond
O
2
Esters
each
−
C
3
O
YOU
to
−
−
CH
esters.
DID
−
and
esters

C
of
above
esters
−
esters
=
present
=
describe
O
−

C
−
−
−
LEARNING
13.6.2
Making
an
ester
Using
the
reaction
of
ethanoic
acid
with
ethanol
as
an
example:
DID
YOU
KNOW?
+
H
CH
COOH
+
C
3
H
2
ethanoic
acid
,
heat
OH
CH
5
COOC
3
ethanol
H
2
ethyl
+
H
5
O
Esters
2
ethanoate
the
acid
When
the
ethanoic
acid
reacts
with
the
alcohol,
water
is
are
ester
or
an
type
of
reaction
is
an
example
of
a
condensation
a
condensation
a
two
small
molecules
join
+
−
O
−
C
2
H
CH
5
3
C
Hydrolysis
is
speeded
by
up
the
of
with
alkanoic
refluxing
vapours
acid
and
of
ester
.
the
+
−
C
2
H
H
−
O
−
H
5
esters
breakdown
reacting
the
of
a
compound
compound
with
by
water.
either
an
Hydrolysis
acid
or
an
is
alkali
13.6.4).
Water
Acid
loss
reaction.
together
O
of
an
O
H
Hydrolysis
Figure
−
H
The
heating
with
molecule.
O
O
(see
of
−
3
C
−
CH
reaction,
(removal)
=
=
elimination
alkali.
the
alcohol,
In
by
reflux
removed.
reduces
This
hydrolysed
under
out
hydrolysis
Condenser
in

The
ester
is
heated
under
reflux
with
a
strong
acid,
e.g.
sulfuric
upright
acid.
position

The

An
reaction
is
reversible.
So
the
ester
is
not
completely
hydrolysed.
Water
alkanoic
acid
and
an
alcohol
are
formed.
For
in
example:
+
H
CH
COOCH
3
methyl
Alkaline
+
H
3
,
reflux
O
CH
2
COOH
+
CH
3
ethanoate
OH
3
ethanoic
acid
methanol
hydrolysis
Ester

The
ester
is
heated
under
reflux
with
a
strong
base,
e.g.
+
aqueous
sulfuric
sodium

The

An
acid
hydroxide.
reaction
is
not
reversible.
So
the
ester
is
completely
hydrolysed.
Heat
alcohol
and
the
salt
of
an
alkanoic
acid
are
formed.
For
example:
Figure
13.6.4
Acid
hydrolysis
of
an
ester
reflux
CH
COOCH
3
+
NaOH
→
CH
3
methyl
COONa
+
CH
3
ethanoate
OH
3
sodium
ethanoate
methanol
EXAM
KEY
POINTS
It
functional
C
present
in
esters
is
O
−
C
the
an
of
2
Esters
are
an
comm
on
that
alkalin
e
formed
by
a
condensation
reaction
between
an
ester
an
alcohol
that
and
a
alkanoic
acid
by
heating
with
a
sulfuric
acid
catalyst.
is
A
condensation
reaction
is
a
reaction
in
which
two
unde
r
together
with
the
elimination
(removal)
of
a
small
with
Hydrolysis
is
the
breakdown
of
a
compound
using
water.
alkalin
e
not
5
6
Acid
hydrolysis
of
an
alcohol.
The
Alkaline
hydrolysis
salt
of
an
reaction
alkanoic
of
ester
does
an
produces
not
ester
go
to
an
alkanoic
the
sodium
of
of
acid
and
an
react
salt
Rem
embe
r
norm
al
alcoho
ls
alkalis
.
do
So
molecule.
alcoho
ls
4
to
molecules
react
join
error
produ
ct
hydro
lysis
alcoho
l.
cond
ition
s
3
a
−
−
O
is
sugg
est
−
−
group
−
The
=
1
TIP
form
ed
not
the
durin
g
hydro
lysis
do
furth
er
.
completion.
produces
an
alcohol
and
the
acid.
129
14
Large
organic
14.1
molecules
Soaps
Natural
LEARNING
Both
At
the
end
of
this
topic
be
able
animal
fats
and
plant
oils
have
ester
links
in
them.
be
made
from
the
esterification
of
glycerol
(which
groups)
with
long-chain
alkanoic
acids,
e.g.
C
H
15
describe
typical
the
structure
of
Figure
a
14.1.1
alkanoic
soap
group)

describe
contains
to:
− OH

Fats
you
can
should
esters
OUTCOMES
the
preparation
of
describe
the
saponification
fats
oils
shows
acid.
of
The
the
the
formula
zig-zag
alkanoic
line
for
both
represents
glycerol
the
COOH.
31
and
carbon
a
long-chain
chain
(alkyl
acid.
a
soap
a

of
b
CH
−
and
−
2
−
CH
OH
OH

compare
the
effect
of
=
−
−
COOH
soapy
CH
and
soapless
detergents
hard
and
their
environmental
soft
water,
including
Figure
H
C
H
C
Figure
H
14.1.2
a
The
formula
alkanoic
14.1.2
shows
of
glycerol,
b
the
simplified
formula
for
a
long-chain
acid
the
formula
for
a
fat.
COOCH
31
15
O
2
−
15
OH
COOCH
31
−
15
14.1.1
impact.
Figure
C
−
2
on
Making
soap
Soaps
sodium
COOCH
31
2
This
fat
has
three
are
or
potassium
salts
of
long-chain
carboxylic
acids.
ester
Fats
and
oils
This
process
can
be
hydrolysed
by
sodium
hydroxide
to
form
soaps.
links.
laboratory
Evaporating
is
called
saponification.
The
method
used
in
the
school
is:
3
10 cm
basin
concentrated
sodium
hydroxide
1
2 cm
vegetable
a
fat
a
or
oil
steam
with
bath)
concentrated
for
15
sodium
minutes
(see
hydroxide
Figure
in
steam
14.1.3).
oil
Steam
Boiling
Heat
(from
3
water
2
Add
3
Stir
4
Let
concentrated
and
the
heat
for
mixture
a
sodium
further
cool.
The
chloride
5
solution
to
the
mixture.
minutes.
soap
forms
on
the
surface
of
the
Heat
mixture.
Figure
14.1.3
The
first
stage
in
making
soap
5
Skim
Figure
DID
YOU
off
14.1.4
r
.t.p.
liquids.
or
fats
are
Fats
solid
may
unsaturated.
be
and
oils
Saturated
C = C
or
lard
to
use
contain
in
C
associated
disease.
vegetable
C = C
cooking
which
H
of
by
sodium
saponification
of
the
fat,
hydroxide.
COOCH
35
It
H
17
is
C
H
contain
a
saturated
+
C
3
NaOH
H
17
C
2
COONa
HOCH
35
COONa
+
35
H
17
2
HOCH
COONa
HOCH
35
2
oils,
double
than
17
COOCH
35
H
C
2
COOCH
35
butter
glyceryl
(a
stearate
+
fat)
sodium
sodium
hydroxide
(a
stearate
soap)
high
Figure
proportion
130
the
mixture.
fats,
double
17
bonds,
for
the
−
been
cardiovascular
which
equation
of
−
have
healthier
the
surface
−
no
stearate
−
with
shows
the
are
17
have
bonds,
from
saturated
C
which
soap
KNOW?
glyceryl
At
the
fats.
14.1.4
Soaps
are
formed
by
the
hydrolysis
of
fats
(or
oils).
+
glycerol
Soapless
A
detergents
detergent
materials.
is
a
substance
Soapless
that
removes
detergents
differ
stains
from
and
soaps
dirt
in
from
the
nature
of
EXAM
the
group
at
the
‘head
end’
of
the
molecule
(see
Figure
Y
ou
a
to
–
TIP
14.1.5).
will
no t
be
remem
ber
expect
ed
the
+
COO
Na
fo rm
ulae
you
O
fo r
shou
ld
soaps
be
but
able
to
b
=
−
explai
n
−
−
−
S
−
O
=
term
s
and
Ionic
14.1.5
a
A
soapy
sulfonate
Water
Soft
In
calcium
well
contains
Detergents
water.
(soap),
b
a
hydr
o lysi
s
equa
tions
which
' head'
soapless
detergent,
which
has
to
are
you.
a
end’
softening
water
salts.
detergent
‘head
ester
fo rm
ulae
given
Figure
of
write
from
' tail'
in
Na
O
Hydrocarbon
saponi
ficatio
n
+
some
and
with
hardly
form
places
the
magnesium
soap.
It
any
lather
forms
dissolved
(foam)
water
salts
a
is
‘hard’
(see
scum
they
Hard
insoluble
or
are
because
17.2).
of
calcium
when
magnesium
shaken
it
with
contains
water
calcium
does
or
soft
dissolved
not
lather
magnesium
KEY
POINTS
salts.
2+
2C
H
17
COONa(aq)
+
Ca
1
+
(aq)
→
(C
35
H
17
COO)
35
Ca(s)
+
2Na
Soaps
are
sodium
potassium
soap
calcium
in
Soapless
because
do
not
detergents
the
make
calcium
form
a
hard
or
ions
soap
chain
better
lather
magnesium
salts
in
hard
formed
water
are
than
soluble.
soaps
So
2
Soap
alkanoic
is
hydrolysis
they
with
scum.
environmental
impact
of
3
detergents
The
to
Most
detergents
are
harmful
to
the
of
long-
acids.
prepared
of
by
fats
or
concentrated
hydroxide
The
salts
scum
water
a
or
(aq)
2
a
oils
sodium
solution.
hydrolysis
make
the
of
soap
fats
is
or
oils
called
environment.
saponification.

Many
detergents,
both
soapy
and
soapless,
cannot
be
decomposed
4
in
the
environment.
They
are
non-biodegradable.
When
water,
detergents
produce
foam
and
soaps
produce
scum.
Both
foam
to
reduce
the
death
the
of
amount
aquatic
of
oxygen
dissolving
in
water
and
so
Detergents
destroy
the
5
organisms.
oily
layer
on
the
surface
to
form.
Hard
water
of
fish,
contains
calcium

them
diseases
and
Low
to

The
and
parasites.
So
more
fish
6
of
detergent
kill
fish
eggs
and
decrease
are
foam
treatment
added
to
soapless
Phosphates
produced
of
Soaps
form
shaken
their
by
sewage
in
can
detergents
sewage
detergents
cause
can
to
improve
eutrophication
reduce
treatment
the
works.
their
(see
effective
16.4).
7
the
and
layer
hard
can
fish
amount
water
oily
of
scum
on
do
cause
by
of
by
when
water
detergents
Detergents
death
a
with
soapless
action.
salts.
get
breed.
Phosphates
cleaning
bacteria
die.
concentrations
ability

from
and
which
magnesium
protects
soft
cause
lead
dissolved

with
detergents
and
lather
scum
shaken
Soapless
the
reducing
oxygen
in
destroying
the
but
not.
surface
the
the
of
fish.
131
14.2
Polymers
Macromolecules
LEARNING
OUTCOMES
Macromolecules
At
the
end
of
this
topic
units.
should
be
able
define

distinguish
and

the
term
between
the
repeating
Plastics,
polymer
condensation
describe
Carbon
a
of
use
units
Polymers
in
molecules
diamond
is
a
made
up
of
repeating
macromolecule
made
up
of
carbon
and
starch
atoms
are
arranged
also
in
tetrahedra
(see
5.5).
macromolecules.
and
polymerisation
are
macromolecules
made
up
by
linking
at
least
50
small
the
called
monomers.
Figure
14.2.1
shows
the
formation
of
polyalkenes
the
state
large
of
polymerisation
molecules

very
form
addition
polymers
involved
formation
the
proteins
Polymers
reactions
in
to:
of

are
you
of
a
polymer
poly(ethene)
from
its
monomers.
named
polyalkene.
Continuation
Repeating
unit
bond
H
−
−
=
C
−
−
C
H
H
H
H
H
German
He
von
was
Pechmann,
heating
a
in
that
substance
addition
was
a
white,
was
to
suggested
substance
in
that
the
It
not
It
an
polymethylene.
until
1933,
industrial
repeating

The
monomers
waxy
form
of
It
by
The
conversion
for
that
There
are
two
C = C
form
the
polymer
poly(ethene).
in
polymers
the
small
either
are
connected
molecules
with
or
that
without
by
covalent
combine
the
bonds.
together
elimination
of
a
to
small
of
monomers
to
polymers
is
called
polymerisation.
of
polymerisation:
polymerisation
double
bond
occurs
combine
to
when
form
monomers
the
polymer
containing
and
no
other
chance!
form
writi
ng
is
formed.
the
polymerisation
polymer
and
a
small
occurs
when
molecule
is
monomers
eliminated
are
(see
linked
14.3).
po lym
er
fo r
an
don’
t
doub
le
sing
le
remem
ber
addi
tion
fo rge
bond
bond
to
t
that
chan
ges
and
draw
‘cont
inua
tion
polymers
the
For
in
the
bond
s’.
addition
double
an
When
polymerisation
bond
adjacent
the
of
each
monomers
can
polymers
based
atoms
are
are
heat
The
are
required
and
a
alkenes,
of
as
the
the
breaks
is
where
− Cl,
in
forms
only
a
a
− CN
or
or
C = C
bond
with
bonds.
poly(alkene).
alkanes.
one
addition
the
single
called
long-chain
as
most
bonds
and
has
polymer
very
such
make
catalyst.
of
formed
monomers
groups
to
one
monomer
alkene
by
occur
,
polymer
thought
on
substituted
conditions
pressure,
be
to
alkene
monomer
.
Poly(alkenes)
The
132
to
TIP
fo rm
ula
a
together
was
Addition
the
bond
the
to
to
are
types
Condensation
When
units
polymer,
compound
EXAM
monomers
was
poly(ethene)
again
Polymer
molecule.
a
discovered,
H
was
however
,
method
the
Addition
production
monomers
Ethene
The
long
chains.
14.2.1


called
H
waxy
products.
contained
hydrocarbon
H
−
and
formed
other
C
chemical
diazomethane
noticed
H
−
C
1898.
Figure
called
−
chemist,
Ethene
Hans
C
−
a
−
C
−
by
−
H
H
chance
C
−
H
−
−
C
−
−
+
H
−
−
H
C
−
=
H
−
C
H
−
+
H
H
−
C
H
−
=
−
C
H
−
by
−
discovered
H
−
was
−
Poly(ethene)
H
−
KNOW?
−
YOU
−
H
DID
Other
more
hydrogen
− OH.
polymers
are
high
of
addition
it
polymer
is
is
formed.
based
Some
on
the
name
examples
are
of
the
given
CH
in
3
H
CH
−
which
−
3
H
14.2.1.
=
C
14.2.1
Some
addition
−
C
C
H
−
−
−
H
T
able
−
C
−
n
−
T
able
an
from
−
name
monomer
−
The
H
H
polymers
n
of
Chemical
name
of
Common
name
monomer
polymer
polymer
ethene
poly(ethene)
polythene
propene
poly(propene)
polypropene
chloroethene
poly(chloroethene)
polyvinyl
of
propene
Figure
poly(propene)
14.2.2
Propene
monomers
together
polymer
=
C
C
−
n
−
polystyrene
H
−
C
C
H
−
−
poly(phenylethene)
−
phenylethene
Cl
H
−
−
Teflon
poly(propene).
Cl
H
poly(tetrafluoroethene)
bond
the
(PVC)
®
tetrafluoroethene
form
−
chloride
to
−
Name
H
H
n
Writing
equations
for
addition
polymerisation
Figure
14.2.3
Forming
poly(chloroethene)
When
such
the
as
simple
monomer
− Cl
way.
− OH,
or
Figure
monomers,
contains
we
can
14.2.2
CH = CH
CH
3
alkyl
groups
represent
represents
,
to
form
or
the
the
other
functional
equation
in
polymerisation
a
groups
relatively
of
propene
KEY
2
1
In
writing
this
POINTS
poly(propene).
equation
we:
Polymers
made
50

draw

put
the
monomer
on
the
left
with
the
side
chains
drawn
are
up
small
by
macromolecules
linking
at
molecules
least
called
vertically
monomers.
a
there
letter
is
a
n
in
large
front
of
number
the
of
formula
of
monomer
the
monomer
to
show
that
2
molecules
Addition
occurs

draw
the
structure
of
the
polymer
after
the
arrow
by
drawing
polymerisation
when
containing
monomer
with
a
single
bond
instead
of
a
double
put
‘continuation

put
square
bonds’
at
both
ends
of
the
through
the
combine
continuation
put
a
letter
n
at
the
bottom
right-hand
corner
to
show
that
polymer
repeats
itself
many
14.2.3
chloroethene
represents
to
form
no
other
formed.
Condensation
polymerisation
times.
occurs
Figure
and
is
the
3
unit
double
form
bonds
compound

to
molecule
the
brackets
C = C
a
bond
bond

monomers
the
the
equation
for
the
polymerisation
of
linked
poly(chloroethene).
and
a
when
to
monomers
form
small
the
are
polymer
molecule
is
eliminated.
Some
uses
of
addition
4
polymers
A
poly(alkene)
formed
from
is
a
polymer
alkene
monomers.

Poly(ethene):
bags,

plastic
clingfilm
Poly(propene):
ropes,
bottles,
wrap
crates
(plastic
for
plastic
wrap)
5
A
shorthand
an
bottles,
addition
draw
carpets
the
Poly(chloroethene),
PVC:
water
cable
pipes,
is
to
unit
single
square
gutters,
with
continuation
insulation
bonds

only
within
brackets
electrical
drawing
pipe
bonds)
fittings,
of
repeating
(containing

way
polymer
Poly(tetrafluoroethene):
and
an
‘n’
at
the
non-stick
bottom
right
of
the
brackets.
pans
6

Poly(phenylethene):
plastic
Figure
expanded
Particular
addition
polymers
toys,
14.2.4
Many
articles
have
specific
uses,
e.g.
PVC
foam
can
be
from
made
is
used
for
water
pipes.
polymers.
133
14.3
Condensation
Condensation
LEARNING
the
end
of
this
topic
condensation
be
able
a
small
describe
of
condensation
describe
the
reactions
water
,
is
formed
hydrogen
reaction
by
the
is
formation
of
the
are
linked
small
together
molecules
in
and
ammonia.
Figure
an
14.3.1,
alkanoic
acid
An
example
where
with
an
an
amide
amine.
O
O
of
polyesters
−
3
C
−
O
H
H
+
N
and
of
a
−
CH
CH
3
C
3
−
An
named
alkanoic
acid
An
CH
3
+
H
2
O
H
H
polyester
−
N
−
use
of
−
a
polyamide,
chloride
shown
reaction
polysaccharides
state
molecules
Examples
polymerisation
CH

monomer
eliminated.
=
the
are
condensation
involved
polyamides,
is
=
in
a
linkage
polymerisation

molecule
to:
eliminated

polymerisation,
you
and
should
polymerisation
OUTCOMES
In
At
polymers
Amide
amine
linkage
and
Figure
14.3.1
When
an
amide
linkage
is
formed,
water
is
eliminated.
polysaccharide.
Condensation
order
each
EXAM
form
polymerisation
a
may
condensation
monomer
must
have
at
least
will
no t
be
linkages
in
condensation
(C )
fo rm
ulae
−
C
groups.
Three
types
to
in
Figure
14.3.2.
−
(C )
(C )
−
C
−
N
−
(C )
(C )
−
−
O
(C )
po lym
ers.
linkage
Amide
linkage
Glycosidic
linkage
howe
ver
,
14.3.2
block
like
Figu
show
ing
displa
yed
shown
H
draw
rams,
O
fo r
Figure
able
are
O
−
Ester
shou
ld,
diag
functional
In
monomers,
expect
ed
fully
cond
ensa
tion
14
.3.4
,
monomers.
different
−
displa
yed
be
different
two
=
the
=
write
Y
ou
two
from
two
polymers
O
to
involve
polymer
TIP
of
Y
ou
to
re
Polyamides
the
fo rm
ula
of
linka
ge.
the
Nylon
acids
is
a
and
polyamide.
diamines.
compounds
In
these
When
− NH
as
in
diagrams
these
We
Figure
the
to
form
monomers
can
represent
for
the
polyamides
structures
are
of
dialkanoic
these
14.3.3.
coloured
molecules
group
The
react,
an
blocks
each
amide
represent
− COOH
linkage
and
the
group
a
rest
of
the
reacts
molecule
molecule.
with
of
an
water
is
2
HOOC
A
COOH
dialkanoic
eliminated
(Figure
14.3.4).
acid
Amide
O
C
−
OH
+
n HN
NH
−
C
C
−
N
H
H
−
−
H
N
−
2
=
=
NH
O
−
N
−
2
=
=
n HO − C
H
O
O
linkage
H
n
A
diamine
Dialkanoic
Figure
acid
Diamine
Polyamide
14.3.3
+
Figure
134
14.3.4
Formation
of
a
polyamide
(2n–1)H
O
2
Polyesters
DID
Terylene
is
a
polyester.
The
monomers
for
polyesters
are
YOU
dialkanoic
Not
acids
and
diols.
When
these
molecules
react,
− COOH
each
KNOW?
all
nylon
is
condensation
reacts
with
− OH
an
group
to
form
an
ester
linkage,
and
a
water
is
eliminated
(Figure
as
Ester
O
O
−
OH
n HO
+
called
−
OH
contains
caprolactam,
C = O
well
as
a
heated
in
an
N − H
an
group
group,
is
nitrogen,
atmosphere
and
the
ring
of
breaks
=
C
ring
linkage
O
=
=
=
n HO − C
A
14.3.5).
which
O
by
reactions.
molecule
compound
of
made
group
C
C
−
O
O
−
at
the
amide
group.
which
are
formed
nylon.
No
other
The
join
chains
to
make
n
Dialkanoic
acid
Diol
Polyester
molecule
is
formed.
+
Figure
14.3.5
Formation
of
a
(2n–1)H
O
2
polyester
a
Polysaccharides
H
−
When
a
(monosaccharide).
polysaccharide.
glucose
molecules
react
Starch
Starch
is
together
is
a
a
polymer
natural
in
the
H
of
−
presence
of
− OH
particular
groups
react
and
form
a
glycosidic
−
OH
O
C
H
linkage.
is
eliminated
(Figure
14.3.7).
C
OH
−
water
H
−
of
−
molecule
−
C
A
O
OH
OH
n
+
O
+
(2n–1)H
−
C
−
C
OH
OH
OH
OH
OH
n
b
H
H
enzymes,
C
plant
−
product.
sugar
is
−
simple
starch
−
a
So
OH
is
glucose.
−
Glucose
OH
H
O
2
n
Figure
Glucose
Glucose
Glycosidic
14.3.6
a
b
Figure
14.3.7
Cellulose
is
glycosidic
used
in
a
polysaccharide
linkage
making
is
slightly
paper,
present
different
cellophane
in
the
to
and
cell
that
in
walls
of
starch.
plants.

uses
of
condensation
Polyamides:
Nylon
carpets
ropes.
and
Polyesters:
towels.
is
T
erylene
Other
used
is
to
used
polyesters
Polysaccharides:
YOU
make
for
are
seatbelts,
fabrics
used
to
Starch
is
used
in
such
make
as
fishing
lines,
bedsheets,
plastic
bottles
clothing,
clothing
and
and
carpets.
glues,
in
papermaking
and
a
linkage.
glycosidic
glyc-
and
means
glycerol
words
together
polymerisation,
and
a
small
monomer
molecule
2
The
linkage
in
polyamides
3
The
linkage
in
polyesters
is
the
4
The
linkage
in
polysaccharides
5
Polyamides,
is
sweet.
are
is
The
Both
sweet.
relating
called
prefix
glucose
There
to
are
sugars
begin
with
glycosides
the
amide
molecules
is
the
ester
of
prefix
glyc-,
the
carbohydrates
and
linkage,
nylon
is
used
to
linkage,
YOU
ropes
and
KNOW?
− COO −.
glycosidic
polysaccharides
make
form
− CONH −
linkage,
− O−
or
as
can
have
exist
branched
as
single
chains.
catalyse
the
chains
Specific
reaction
particular
causing
e.g.
that
are
enzymes
polyesters
particular
compounds.
Starch
is
are
eliminated.
DID
uses,
linkage
for
types
condensation
linked
molecules
the
clothes.
POINTS
In
glucose
polymerise,
ring
1
KNOW?
polymers
e.g.
KEY
of
is
that
stiffening
structure
rayon.
many

molecule,
The
Cellulose
When

glucose
simplified
glucose
DID
Some
A
linkage
branches
to
form.
clothes.
135
Section
SECTION
1
From
B:
the
which
B
Practice
Multiple-choice
four
pair
of
homologous
compounds
compounds
exam
questions
shown,
identify
belongs
to
the
4
same
When
a
series.
gas
sodium
is
H
−
H
C
=
a
−
C
−
C
The
−
−
−
H
H
gas
with
H
−
C
produces
milky
white
precipitate
a
limewater.
The
gas
makes
a
‘popping’
sound
H
H
III
The
gas
rekindles
−
C
O
−
H
d
The
gas
turns
a
a
glowing
splint.
damp
blue
litmus
paper
red.
H
Which
of
the
for
following
the
is
reaction
the
of
correct
balanced
ethanoic
acid
IV
with
a
I
and
II
b
I
and
III
a
magnesium
Mg(OH)
+
hydroxide?
2CH
2
COOH
→
3
Mg(CH
COO)
3
and
with
splint.
c
equation
II
is
−
H
−
−
−
−
H
−
C
5
c
gas
−
H
H
−
−
−
C
−
−
−
H
H
−
C
H
H
−
−
C
H
−
−
−
C
this
II
−
−
when
indicated?
lighted
H
following
made
H
b
I
H
be
ethanol,
the
H
H
H
would
with
of
−
−
C
as
reacts
Which
H
−
−
C
H
−
=
C
H
−
−
C
−
−
−
−
H
H
metal
produced.
observations
tested
H
H
H
questions
IV
b
MgOH
+
CH
COOH
+
2H
2
O
2
→
3
d
III
and
Mg(CH
IV
c
2
Which
of
the
following
equations
Mg(OH)
+
CH
2
correctly
the
complete
combustion
of
COOH
C
H
4
+
5O
8
→
3CO
2
+
4H
2
Mg(OH)
+
2CH
2
O
COO)
COOH
H
4
+
6O
8
→
4CO
2
C
H
4
+
+
4H
2
9O
10
→
→
3
COO)
+
2
+
5H
2
Propene
is
converted
to
polypropene
by
O
2
the
following
types
of
reaction?
1
3
+
Which
the
Cl
is
the
chlorine
product
in
H
the
Cl
−
H
H
−
C
=
C
a
Dehydrogenation
b
Hydrogenation
c
Addition
d
Condensation
when
dark?
polymerisation
Cl
−
C
O
2
−
−
5H
−
C
with
+
2
−
=
4CO
H
−
−
C
→
2
following
reacts
Cl
−
O
2
of
propene
H
6
10
−
C
−
−
−
H
polymerisation
H
7
Which
of
the
following
molecules
alkanoic
a
b
H
−
Cl
C
−
−
−
C
CH
O
−
=
3
H
a
b
H
d
H
H
=
−
C
2
H
−
C
−
C
−
−
O
−
CH
CH
3
H
3
H
c
O
−
C
CH
−
−
−
−
H
136
O
H
−
H
O
H
C
C
−
−
H
−
−
C
H
O
−
−
C
−
H
−
H
H
−
c
−
−
H
C
−
C
−
−
−
−
H
C
−
−
−
C
−
−
−
−
H
Cl
H
H
−
−
−
H
Cl
an
acid?
H
Cl
is
H
=
H
4
=
C
4H
O
2
O
of
d
O
2
2
4CO
2
H
2
6
c
+
2
3
C
O
2
3
Mg(CH
b
H
→
butane?
d
a
+
3
Mg(CH
shows
COO)
3
d
H
which
SECTION
8
a
B:
Short
Compounds
answer
A
(C
H
4
)
questions
and
B
(C
10
H
5
)
are
a
On
what
physical
property
of
the
12
hydrocarbons.
hydrocarbons
does
fractional
distillation
depend?
i
Draw
possible,
structures
of
fully
(1)
displayed
compounds
A
and
B.
(2)
b
Explain
how
fractional
hydrocarbons
ii
State
the
names
structures
iii
State
the
series
to
that
that
you
name
which
of
match
have
the
different
separates
fractions.
(4)
the
drawn.
(2)
c
homologous
compound
into
distillation
A
Give
a
use
of:
i
the
naphtha
ii
bitumen
fraction
belongs.
fraction
(2)
(1)
d
b
Anaerobic
fermentation
production
i
Define
of
is
used
in
Some
longer-chain
alkanes
are
cracked
to
the
produce
shorter-chain
i
do
alkanes
and
alkenes.
wines.
anaerobic
fermentation.
Why
oil
companies
carry
out
(2)
cracking?
ii
Write
a
balanced
chemical
ii
for
the
reaction
occurring
What
conditions
fermentation.
one
reason
why
Write
an
not
suitable
C
H
Esters
can
fermentation?
undergo
hydroxide
other
hydrolysis
in
State
one
other
method
of
Alcohols
of
and
26
compound
containing
three
atoms.
(2)
are
a
homologous
which
are
series
more
of
volatile
in
water
than
the
alkanes
and
with
more
the
(1)
same
the
hexane
hydrolysing
esters.
Draw
cracking
solution.
soluble
ii
the
form
aqueous
compounds
i
for
to
(1)
10
sodium
,
for
carbon
c
(2)
equation
12
are
one
anaerobic
for
high
dodecane,
temperatures
needed
cracking?
(2)
iii
State
are
during
catalytic
iii
(2)
equation
the
fully
products
reaction
of
displayed
of
the
ethyl
structures
alkaline
number
of
carbon
atoms.
of
a
What
is
b
Explain
the
meaning
of
the
is
less
term
volatile?
(1)
hydrolysis
ethanoate.
why
ethanol
volatile
than
(2)
ethane.
(3)
H
=
−
O
c
H
−
C
H
−
O
−
C
−
water
−
C
−
H
ethanol
is
more
soluble
in
ethane.
(4)
d
Ethanol
is
manufactured
by
the
hydration
H
of
ethyl
why
than
H
−
H
Explain
NaOH
−
C
−
−
−
H
ethene.
ethanoate
i
What
conditions
are
needed
for
this
hydration?
d
i
Define
ii
The
polymerisation.
ii
figure
below
represents
Give
two
What
type
of
advantages
by
hydration
N
(1)
−
−
C
e
i
O
Write
an
sodium
ii
H
it
by
fermentation.
O
−
equation
with
for
the
reaction
(1)
Explain
the
why
reaction
the
in
organic
part
i
is
product
soluble
of
in
water.
State
the
type
of
polymer
that
formed.
Write
an
Petroleum
contains
many
different
are
for
the
reaction
of
separated
by
fractional
with
ethanoic
acid
and
name
hydrocarbons,
the
which
equation
(1)
butanol
9
(1)
would
iii
be
of
propanol.
H
monomer
iii
(2)
shown
−
−
monomer
undergo?
−
H
the
=
below
would
manufacturing
over
polymerisation
manufacturing
reaction
of
a
ethanol
monomer.
(3)
(1)
organic
product
(2)
distillation.
137
15
Metals
15.1
Properties
Physical
LEARNING
the
end
should

be
of
the
chemical

describe
water,
and
this
able
describe
of
metals
metals
OUTCOMES
Most
At
properties
of
topic
properties
the
action
dilute
dilute
the
following
physical
properties:
They
are
good
conductors
of
electricity.

They
are
good
conductors
of
heat.
metals

They
are
malleable:
oxygen,

They
are
ductile:

They
are
lustrous:
and
of
of
hydrochloric
sulfuric
have

to:
physical
metals
you
acid
acid
they
they
can
can
they
be
be
beaten
drawn
have
a
into
into
shiny
different
shapes.
wires.
surface
when
freshly
cut.
on
In
addition,
the
transition
metals
have
the
following
physical
metals.
properties:
3

They
have

They
are

They
have

They
are
T
able
a
density:
sonorous:
high
they
melting
they
ring
have
a
when
points
and
high
hit
mass
with
boiling
a
per
hard
cm
of
metal.
object.
points.
hard.
15.1.1
T
able
high
shows
15.1.1
the
Physical
Metal
physical
properties
of
properties
some
Melting
Density
point
(g cm
of
some
metals.
metals
Relative
tensile
Hardness
–3
Figure
15.1.1
A
wide
are
variety
made
of
from
(ºC)
)
strength
objects
metals.
Sodium
98
0.97
<1
Very
be
soft
cut
(can
with
a
knife)
EXAM
W he
n
qu es
ph ys
of
an sw
tio ns
ic al
se lec
ar e
e
t
th em
.
ha s
ls
th e
es t
a
ab ou
in
su re
It
er ing
pr o pe
co m m
su gg
649
1.74
4
Fairly
hard
Aluminium
660
2.70
7
Fairly
hard
Iron
1535
7.86
21
Hard
Copper
1083
8.92
13
Hard
420
7.14
11
Fairly
TIP
me ta
m ak
Magnesium
pr o pe
is
hi gh
ra l ,
al l
The
of
yo u
rt ies
to
in co
th at
Zinc
th e
ge ne
th at
on
t
th at

of
rr ec t
to
list
below
some
The
t
an d
physical
properties

All

Tin
Group
I
metals
information
about
the
physical
properties
of
calcium
are
similar
to
those
of
are
soft
and
have
a
very
low
density.
and
lead
are
fairly
soft
metals.
They
are
harder
than
sodium
ing
ha rd
than
magnesium
and
calcium.
.

Mercury

Most
is
a
metals
liquid
are
pinkish-brown
138
further
so di um
melt
is
gives
metals.
magnesium.
softer
po in
hard
rt ies
at
r.t.p.
silvery
in
in
colour.
colour
when
freshly
cut.
Copper
is
but
Chemical
Action
Most
of
properties
of
metals
oxygen
metals
react
with
2Mg(s)
oxygen
+
O
(g)
or
air
→
to
form
oxides,
e.g.
2MgO(s)
2
magnesium
4Al(s)
magnesium
+
3O
(g)
→
2Al
2
Metals
low
in
the
O
2
aluminium
(s)
3
aluminium
electrochemical
oxide
series,
oxide
e.g.
gold,
do
not
react
(see
15.3).
Action
Metals
of
water
high
in
the
electrochemical
series
react
with
cold
water.
A
DID
metal
hydroxide
and
hydrogen
are
formed,
YOU
Iron(II,III)
2Na(s)
+
2H
O(l)
→
KNOW?
e.g.
2NaOH(aq)
+
H
2
oxide,
Fe
O
3
(g)
,
can
be
4
2
thought
sodium
sodium
of
as
a
combination
hydroxide
of
the
oxides
FeO
and
Fe
O
2
+
2H
O(l)
→
Ca(OH)
2
(aq)
+
H
2
calcium
calcium
(g)
It
meals
slightly
lower
in
the
both
ions.
hydroxide
electrochemical
series,
It
is
found
a
black
or
iron,
react
very
slowly
or
not
and
Fe
at
all
with
powder
naturally
as
the
and
main
e.g.
component
magnesium
3+
Fe
2
is
Reactive
contains
.
3
2+
Ca(s)
water
.
They
of
the
mineral
may
magnetite.
react
with
hot
water
or
Mg(s)
+
steam
H
to
O(l)
form
→
a
metal
MgO(s)
oxide
+
H
2
magnesium
and
hydrogen.
(g)
2
warm
magnesium
water
oxide
KEY
1
3Fe(s)
+
4H
O(g)
→
Fe
2
O
3
(s)
+
4H
4
POINTS
Metals
and
iron
steam
iron(
II
III)
lower
than
hydrogen
in
the
are
electrochemical
series
do
not
conductors
and
ductile.
Transition
metals
are
hard,
react
have
with
good
malleable
oxide
2
Metals
are
(g)
2
high
melting
points
water.
and
Action
of
dilute
have
Oxygen
metals
above
densities.
acids
3
Metals
high
hydrogen
in
the
electrochemical
series
react
with
reacts
to
with
form
the
most
metal
dilute
oxide.
hydrochloric
They
also
acid
react
to
form
with
the
dilute
metal
sulfuric
chloride
acid
to
(a
salt)
form
the
and
hydrogen.
metal
sulfate
(a
4
salt)
and
hydrogen.
Examples
Water
high
in
series
Zn(s)
+
reacts
2HCl(aq)
→
ZnCl
(aq)
+
H
2
the
to
form
Mg(s)
+
hydrochloric
zinc
acid
chloride
H
SO
2
(aq)
→
MgSO
4
(aq)
+
H
4
Some
magnesium
(g)
acid
sulfate
and
calcium
with
so
is
never
carried
out
in
a
dilute
acids
can
Metals
such
as
copper,
the
school
above
series
silver
than
and
gold,
hydrogen,
which
do
hydrogen
electrochemical
react
with
or
dilute
sulfuric
acid
laboratory.
are
lower
in
form
not
react
with
the
corresponding
the
salt
electrochemical
with
metal
be
to

the
hydrogen.
hydrochloric
explosive,
react
form
and
Metals
series
sodium
to
hydrogen
Note:
of
metal
hydrogen.
2
sulfuric
in
reaction
metals
steam
6
The
and
hydrogen
oxide

the
(g)
5
magnesium
metals
electrochemical
2
hydroxide
zinc
with
are:
(chloride
or
sulfate)
and
dilute
hydrogen.
hydrochloric
or
sulfuric
acid.
139
15.2
Reactions
metal
Reaction
LEARNING
the
end
of
this
topic
be
able
describe
the
metal
reaction
oxides
a
react
salt
and
be
with
and
speeded
the
dilute
sulfuric
reactions
hydroxides
hydrochloric
dilute
hydrochloric
Some
of
the
acid
or
reactions
dilute
may
be
sulfuric
slow.
acid
They
by
heating.
dilute
hydrochloric
acid
a
metal
chloride
and
water
are
formed.
example:
acid
+
2HCl(aq)
→
ZnCl
of
(aq)
+
H
2
oxide
zinc
O(l)
2
chloride
with
acid
and
With
sulfuric
acids
dilute
zinc
metallic
with
water.
up
ZnO(s)
describe
with
of
For
hydrochloric

oxides
to:
With
metallic
oxides
form
can

compounds
you
to
should
some
OUTCOMES
Metal
At
of
of
dilute
sulfuric
acid
a
metal
sulfate
and
water
are
formed.
For
acid
example:

describe
the
action
of
heat
Al
O
2
on
metal
nitrates,
(s)
and
3H
SO
2
aluminium
hydroxides
+
3
(aq)
→
Al
4
(SO
2
oxide
Reaction
of
Many
hydroxides
metal
acid
examples
With
For
to
of
+
3H
O(l)
2
sulfate
dilute
metal
form
hydroxides
react
the
with
dilute
corresponding
neutralisation
hydrochloric
reactions
acid
a
with
hydrochloric
salt
(see
metal
acids
and
acid
water.
or
dilute
These
are
7.6).
chloride
and
water
are
formed.
example:
Ca(OH)
(s)
+
2HCl(aq)
→
CaCl
2
calcium
With
YOU
(aq)
3
aluminium
oxides.
sulfuric
DID
)
4
carbonates,
dilute
(aq)
+
2H
2
hydroxide
calcium
sulfuric
acid
a
metal
sulfate
O(l)
2
chloride
and
water
are
formed.
For
KNOW?
example:
The
correct
chemical
name
2NaOH(aq)
+
H
SO
2
for
sodium
nitrate,
NaNO
,
sodium
nitrate(V).
chemical
nitrite,
name
NaNO
,
The
for
is
(aq)
→
Na
4
SO
2
(aq)
+
2H
4
O(l)
2
is
3
sodium
hydroxide
sodium
sulfate
correct
sodium
Reaction
sodium
of
metal
carbonates
with
acids
2
nitrate(III).
We
do
not
always
Metal
use
the
correct
acid
names,
however
,
because
to
are
so
well
form
the
For
their
dioxide,
gas
old
the
given
other
names.
than
when
Group
heated,
is
I
zinc
brown
carbon
acid
dioxide
or
dilute
and
sulfuric
water
(see
+
H
SO
2
(aq)
→
ZnSO
4
(aq)
+
CO
4
carbonate
zinc
(g)
2
+
H
O(l)
2
sulfate
nitrates
properly
action
of
heat
on
some
metal
compounds
called
metal
nitrates,
carbonates,
hydroxides
and
oxides
break
down
oxide.
on
140
hydrochloric
salt,
nitrates
Some
nitrogen(IV)
(s)
3
The
are
dilute
known
Nitrogen
poisonous
off
with
example:
ZnCO
by
react
corresponding
these
7.3).
compounds
carbonates
chemical
heating.
We
call
this
type
of
reaction
thermal
decomposition.
Thermal
All
decomposition
nitrates
the
decompose
decomposition
of
when
nitrates
heated.
products,
There
depending
are
on
some
the
differences
reactivity
of
the
in
metal
EXAM
in

the
The
metal
TIP
nitrate.
nitrates
decompose
of
to
Group
form
I
metals
the
apart
metal
from
nitrite
and
lithium
Mak
e
nitrate
oxygen,
For
the
example:
(s)
2NaNO
3
sodium
(s)
+
O
The
nitrates
oxide,
2
nitrate
of
sodium
most
nitrogen
other
dioxide
nitra
tes
2
nitrite
of
oxygen
o ther
metals
decompose
(nitrogen( IV)
oxide)
to
and
form
the
write
fo r
)
3
2CuO(s)
nitrates
metal,
copper( II)
of
+
very
unreactive
dioxide
and
Grou
p
O
from
I
nitra
tes.
be
these
Y
ou
able
balanc
ed
those
to
equa
tions
react
ions.
(g)
2
nitrogen
oxide
nitrogen
(g)
2
nitrate
The
4NO
2
copper( II)

+
how
therm
al
of
differ
also
metal
oxygen:
heat
2Cu(NO
of
know
(g)
shou
ld

you
decom
positio
n
heat
2NaNO
sure
produc
ts
oxygen
dioxide
metals
decompose
to
form
the
oxygen.
heat
2AgNO
2Ag(s)
+
2NO
3
silver(
)
(g)
+
O
2
nitrate
silver
(g)
KEY
POINTS
2
nitrogen
oxygen
1
Metal
oxides
and
metal
dioxide
hydroxides
react
hydrochloric
Thermal
decomposition
of
carbonates
decompose
acid
when
heated
to
form
the
metal
carbon
dioxide.
For
dilute
dilute
acid
to
form
the
oxide
corresponding
and
or
carbonates
sulfuric
Many
with
metal
salt
example:
and
water.
heat
2
CaCO
(s)
CaO(s)
+
CO
3
Metal
acids
Group
I
calcium
calcium
carbon
carbonate
oxide
dioxide
carbonates
carbonate,
Na
carbonates
CO
2
,
apart
do
from
not
lithium
dioxide
carbonate,
decompose
on
to
e.g.
3
sodium
and
Thermal
is
heating.
form
the
decomposition
metal
water
are
salt,
with
carbon
water.
decomposition
down
of
a
3
of
metal
hydroxides
and
hydroxides
formed.
For
decompose
on
heating.
A
by
heating.
oxides
4
Most
a
breaking
compound
Thermal
react
(g)
2
metal
oxide
Group
to
and
I
form
nitrates
a
whereas
example:
decompose
nitrite
most
decompose
and
other
to
from
oxygen
nitrates
an
heat
Zn(OH)
(s)
ZnO(s)
+
H
2
oxide,
O(g)
nitrogen
dioxide
and
2
oxygen.
zinc
hydroxide
zinc
oxide
5
Group
II
hydroxides
decompose
in
a
similar
way.
Most
Group
I
Most
metal
decompose
hydroxides
do
not
decompose.
Lithium
hydroxide
is
an
exception.
to
lithium
oxide
and
oxides
do
not
decompose
when
heated.
A
few
example
is
the
oxides
of
silver( )
metals
do
decompose.
to
an
oxide
and
water.
Metal
An
carbonates,
apart
of
from
unreactive
heating
water.
6
Most
on
It
form
decomposes
hydroxides
metal
Group
I
carbonates,
decomposition
decompose
to
and
dioxide.
form
an
oxide
oxide:
carbon
heat
2Ag
O(s)
2
4Ag(s)
+
O
(g)
2
141
15.3
Metals
and
the
electrochemical
The
LEARNING
the
end
of
this
topic
be
9.3
we
able
describe
metals
the
oxygen,
ease
their
reactivity
based
reactions,
of
on
and
the
the
As
more
ease
relative
the
with
losing
of
go
deduce
can
different
be
placed
metal
in
salts.
order
The
of
reactivity
by
electrochemical
series
of
up
and
which
electrons
reactivity
the
of
metals,
electrochemical
become
stronger
reactivity
carbon
when
of
and
the
the
reducing
the
metals.
hydrogen
reacting
with
series
with
agents.
It
act
also
as
metal
most
reactive
metals
lose
Figure
includes
reducing
oxides
(see
at
the
electrons
15.3.1
the
relative
agents
by
15.4).
carbonates,
and
the
metals
with
relative
oxides
Reactivity

that
order
we
readily
shows
with
decomposition
nitrates,
top.
of
displacement
reaction
hydroxides
saw
metals
to:
shows

revisited
you
reacting
should
series
OUTCOMES
In
At
electrochemical
series
order
based
on
displacement
reactions
of
2+

reactivity
of
metals
based
Zinc
will
reduce
the
Cu
ions
2+
experimental
results
or
in
copper( II)
sulfate:
on
Zn(s)
data
+
Cu
2+
(aq)
→
Zn
(aq)
+
Cu(s)
supplied.
So
zinc
is
above
copper
in
the
electrochemical
series.
2+

Magnesium
will
reduce
the
Zn
ions
2+
Mg(s)
evitcaer
So
+
Zn
magnesium
in
zinc
sulfate:
2+
(aq)
is
→
above
Mg
zinc
(aq)
in
the
+
Zn(s)
electrochemical
series.
K
2+

Silver
will
not
react
with
the
Cu
ions
in
copper( II)
sulfate.
Ca
eroM
So
silver
is
below
copper
in
the
electrochemical
series.
Mg
By
Al
carrying
put
the
out
a
elements
series
in
of
the
displacement
order
of
their
reactions
reactivity:
like
this,
we
magnesium
can
(most
C
reactive)
>
zinc
>
copper
>
silver.
Zn
Fe
Reaction
with
oxygen
Pb
T
able
15.3.1
react
with
shows
some
observations
made
when
different
metals
oxygen.
H
T
able
Cu
Ag
Figure
15.3.1
Electrochemical
including
series
carbon
15.3.1
Reaction
of
some
Metal
Reactivity
Aluminium
A
Copper
Does
Iron
Burns
Gold
Does
Magnesium
A
thin
with
ribbon
not
metals
with
oxygen
burns
burn
oxygen
but
rapidly
its
surface
turns
black
and
only
when
it
is
in
powder
form
or
as
iron
wool
hydrogen
From
these
not
thin
results,
react
ribbon
we
can
burns
put
very
these
rapidly
metals
in
the
following
order
of
reactivity:
magnesium
most
142
reactive
aluminium
iron
copper
gold
least
reactive
Ease
of
thermal
decomposition
EXAM
The
more
nitrate,
lowest
reactive
a
carbonate
metal,
or
temperatures
the
more
hydroxide
at
which
on
difficult
heating.
some
it
is
to
T
able
Group
II
decompose
15.3.2
shows
carbonates
TIP
its
Rem
embe
r
the
easie
r
decompose
the
decom
posit
ion
significantly.
nitra
te
T
able
15.3.2
Decomposition
temperatures
of
some
Decomposition
temperature
Barium
Calcium
Magnesium
Strontium
carbonate
carbonate
carbonate
carbonate
1360
or
900
540
the
1280
less
meta
l.
error
more
It
to
magnesium
So
the
order
you
can
(easiest
of
the
to
see
that
the
decompose)
metal
order
→
reactivity
of
calcium
ease
→
of
decomposition
(most
reactive)
→
strontium
is
strontium
→
a
observations
sugg
est
when
on
the
different
more
have
that
readi
ly.
barium.
is:
>
amount
nitrates
that
meta
ls
compo
unds
calcium
→
magnesium
(least
15.3.4
Reaction
of
nitrogen
undergo
dioxide
thermal
of
some
metals
reactive)
(brown
hydrochloric
acid
gas)
Metal
produced
the
comm
on
with
Some
meta
l
is:
T
able
barium
a
reacti
ve
reacti
ve
meta
l
(ºC)
data,
of
carbon
ate
decom
pose
the
the
carbonates
is,
Carbonate
From
that
therm
al
decomposition
Reactivity
with
is
hydrochloric
shown
in
T
able
Calcium
T
able
15.3.3
Effect
of
Nitrate
Barium
acid
15.3.3.
nitrate
heating
on
Effect
of
Hardly
some
Bubbles
very
nitrates
produced
rapidly
Copper
No
reaction
Magnesium
Bubbles
heating
any
brown
gas
is
produced,
even
produced
on
steadily
strong
heating.
Zinc
Copper(II)
nitrate
Large
amounts
of
brown
gas
are
produced
Bubbles
produced
on
slowly
gentle
Magnesium
nitrate
Some
heating.
brown
gas
is
produced
on
strong
heating.
KEY
1
From
this
information,
you
can
see
that
the
order
of
reactivity
of
POINTS
The
order
metals
metals
can
barium
(most
reactive)
→
magnesium
→
copper
(least
information
can
be
obtained
from
the
ease
of
decompose
of
hydroxides.
barium
hydroxide
A
high
temperature
(barium
is
very
is
needed
is
needed
to
decompose
reactive)
zinc
The
hydroxides
decompose.
This
is
of
the
because
Group
the
I
metals
but
a
hydroxide
Group
I
(apart
metals
reactivity
be
from
are
is
with
acids
metals
to
above
produce
some
from
metals
the
of
reaction
of
the
metals
less
lithium)
very
of
deduced
relatively
(zinc
oxygen
or
acids.
do
3
reactive.
The
reactivity
can
be
of
of
deduced
some
from
metals
the
decomposition
of
acids
their
Only
by
displacement
metals.
can
ease
Reaction
of
The
with
reactive).
the
to
rate
temperature
to
thermal
2
decomposition
not
of
deduced
reactive)
reactions
lower
reactivity
be
is:
reference
Similar
of
the
hydrogen
hydrogen
in
gas.
the
By
electrochemical
observing
the
series
reaction
react
of
nitrates,
carbonates
or
hydroxides.
with
different
4
The
greater
the
ease
of
–3
metals
with
1 mol dm
hydrochloric
acid,
we
can
deduce
the
order
of
decomposition
reactivity
of
the
metals
(T
able
(most
reactive)
→
metal
15.3.4):
nitrates,
calcium
of
magnesium
→
zinc
→
copper
(least
reactive)
carbonates
hydroxides,
reactivity
of
the
the
or
lower
is
the
metal.
143
15.4
Extraction
and
The
LEARNING
the
end
be
of
this
topic
relate
able
the
metal
metals
can
to
carry
carbon
out
the
since
reduction
carbon
of
iron( III)
releases
oxide
electrons
to
iron
better
by
than
heating
iron.
If
we
to:
the
its
extraction
position
electrochemical
at
Figure
copper
principles
underlying
a
of
you
look

aluminium
extraction
with
should
iron
OUTCOMES
We
At
of
in
since
of
and
they
15.3.1
silver
are
(in
could
lower
15.3),
be
than
we
can
extracted
carbon
in
see
from
the
that
zinc,
their
iron,
oxides
lead,
using
electrochemical
carbon
series.
For
example:
the
series
PbO(s)

describe
the
extraction
of

describe
the
extraction
of
+
C(s)
→
Pb(s)
+
CO(g)
iron
In
the
from
laboratory,
their
oxides
unreactive
using
metals
hydrogen.
such
as
Copper
copper
is
below
can
be
extracted
hydrogen
in
the
aluminium.
electrochemical
hydrogen
Waste
over
CuO(s)
series.
heated
+
H
So
copper( II)
copper
(g)
→
oxide
can
be
reduced
by
passing
oxide:
Cu(s)
+
H
2
O(g)
2
gases
Metals
above
extracted
than
Hopper
are
for
iron
ore,
and
limestone
is
by
carbon
in
electrolysis
carbon.
extracted
So
the
electrochemical
because
aluminium
using
they
and
are
series
better
are
at
usually
releasing
magnesium,
among
are
coke
electrons
other
metals
electrolysis.
coke
The
The
extraction
raw
materials
limestone
of
for
(calcium
iron
making
iron
carbonate)
and
iron
air.
ore,
The
(carbon),
commonest
ore
of
iron
is
250 °C
Fire
brick
haematite,
which
is
largely
iron( III)
oxide,
Fe
O
2
lining
in
550 °C
a
blast
furnace
monoxide,
The
(Figure
which
reactions
is
15.4.1).
formed
producing
by
iron
The
main
reactions
.
The
iron
is
extracted
3
reducing
within
the
agent
is
carbon
furnace.
are:
1100 °C
Air
blast
Air
blast
1500 °C
Molten
Slag
out
Iron
slag

Coke
burns

Carbon
in
a
dioxide
hot
blast
reacts
of
with
air
to
coke
form
to
carbon
form
dioxide.
carbon
monoxide:
out
CO
(g)
+
C(s)
→
2CO(g)
2
Molten
iron

Figure
15.4.1
A
blast
furnace
extracting
iron
Carbon
monoxide
reduces
iron( III)
oxide
to
iron:
for
from
iron
ore
Fe
O
2
The
iron
(s)
+
3CO(g)
→
2Fe(l)
+
3CO
3
(g)
2
flows
to
the
bottom
of
the
furnace
and
is
removed
periodically.
Iron
to

ore
the
contains
furnace
Limestone
calcium
to
silicon( IV)
remove
(calcium
Metal
huge
144
ores
are
extracted
quantities.
in
carbonate)
(s)
3
15.4.2
as
an
impurity.
impurity.
The
→
decomposes
CaO(s)
+
CO
(g)
2
Limestone
reactions
oxide:
CaCO
Figure
oxide
this
on
is
involved
heating
to
added
are:
form

Calcium
oxide
reacts
with
the
silicon( IV)
oxide
to
form
calcium
Electrolyte
silicate
(slag).
(molten
CaO(s)
+
(l)
SiO
→
CaSiO
2
aluminium
oxide
+
cr yolite)
(l)
–
3
+
Graphite
The
the
liquid
slag
furnace
is
and
less
dense
forms
a
than
layer
iron.
above
It
flows
the
iron.
to
the
The
bottom
slag
is
run
anode
of
off
Graphite
periodically.
cathode
The
extraction
of
aluminium
Molten
Aluminium
electrodes
narrow
is
extracted
(Figure
cells
by
electrolysis
15.4.3).
with
many
The
using
electrolysis
carbon
is
(graphite)
carried
out
in
aluminium
long,
electrodes.
Figure
15.4.3
A
cross-section
used
Aluminium
oxide
is
purified
from
its
ore
(bauxite).
Aluminium
in
the
of
the
extraction
cell
of
oxide
aluminium
has
a
keep
be
very
the
high
melting
aluminium
molten
for
point
oxide
electrolysis
(2040 ºC).
molten
to
at
occur.
It
this
So
is
difficult
and
temperature.
the
mineral
expensive
But
cryolite,
it
needs
Na
AlF
3
added.
lowers
The
When
the
molten,
melting
reactions
at
the
point
the
cryolite
of
the
electrodes
dissolves
electrolyte
the
to
aluminium
about
to
to
,
is
6
oxide
and
900 ºC.
EXAM
TIP
are:
Y
ou
do
no t
have
to
3+

Cathode:
Al
Aluminium
sinks
the
to
cell
ions
the
or
+
3e
are
→
reduced
bottom
of
siphoned
the
remem
ber
Al
to
cell
aluminium.
and
is
The
tapped
molten
off
at
the
purifi
catio
n
aluminium
bottom
or
of
Anode:
techn
ical
the
off.
blast
the
2−

2O
→
O
+
de tails
of
de tails
furn
ace
electro
lysis
4e
of
the
baux
ite
of
or
cell
fo r
2
produc
ing
Oxide
ions
are
oxidised
to
oxygen
gas.
As
the
hot
oxygen
gas
Y
ou
bubbles
off,
it
reacts
with
the
graphite
anodes
to
form
be
The
The
graphite
anodes
away’
and
eventually
have
reaction
for
this
O
2
KEY
electrolysis
Metals
below
Metals
→
4Al
+
3O
3
2
carbon
extracted
above
extracted
in
by
the
electrochemical
heating
with
series
DID
are
YOU
by
carbon
in
the
In
the
blast
reactivity
series
are
generally
reducing
iron( III)
oxide
is
reduced
by
formed
within
the
limestone
heating
oxide
to
added
form
impurities
to
the
iron(III)
is
above
blast
oxide,
to
slag.
furnace
which
decomposes
reacts
with
on
high
silicon( IV)
Aluminium
in
the
is
extracted
6
Molten
melting
oxide
cryolite
point
in
by
the
cryolite
electrolysis
dissolves
of
the
using
of
the
graphite
aluminium
series.
of
iron
in
so
that
the
At
the
and
iron
the
very
relative
hydrogen
electrochemical
series
reaction
molten
becomes
aluminium
to
though
hydrogen
temperatures,
positions
change
5
oxide
even
of
furnace.
calcium
form
been
possibility
hydrogen
electrochemical
The
have
the
carbon
iron
monoxide
chemists
researching
electrolysis.
furnace,
KNOW?
carbon.
using
4
the
is:
Some
3
and
POINTS
generally
2
conc
entra
te
proces
ses
to
replaced.
overall
the
equa
tions
.
2Al
1
‘burn
shou
ld
carbon
on
dioxide.
alum
iniu
m.
possible.
electrodes.
oxide
and
lowers
the
electrolyte.
145
15.5
Uses
and
of
metals
alloys
Alloys
LEARNING
OUTCOMES
An
At
the
end
of
this
topic
or
should
be
able
alloy
a
explain
often
why
used
relate
metal
in
the
alloys
place
of
properties
aluminium,
their
alloys
mixture,
of
one
are
metals
a
metal
second
The
iron
to
and
their
have
a
metal,
atoms
of
they
regular
the
lead
the
are
15.5.1
Alloying
alloy
crysta
ls.
is
no t
of
of
by
the
in
althou
gh
of
part
a
metals
or
metals
smaller
second
smaller
A
For
pure
arrangement.
metal
or
of
the
disrupt
larger
metal
has
a
arrangement
has
particular
example,
when
a
from
which
atoms
structure.
lattice
metals
atoms
in
a
When
a
lattice
becomes
the
(Figure
metal
regular
is
alloyed
less
with
regular.
arrangement
15.5.1).
regular
is
arrangement
of
atoms.
b
In
alloys
the
disrupted.
advantages
alloys
are
often
in
terms
stronger
of
metallic
and
This
force
of
one
reduces
is
they
of
the
applied
are
the
made.
metals
ability
(Figure
of
The
presence
harder
disrupts
the
layers
the
to
of
the
than
regular
slide
larger
metallic
over
each
other
15.5.2).
mixtu
res,
diffi
cult
we
to
differe
nt
an
phys
ical
pure
more
The
Force
quite
me ta
ls
or
me ta
l.
most
separa
te
by
fo rm
ano th
er
is
two
just
atom
s
crysta
l
Unlik
e
it
of
non-metal.
me ta
l
T
he
me ta
l
the
a
uses.
the
of
lattice,
with
TIP
mixtu
re
one
metallic
and
properties.
a
a
metals
arrangement
regular
An
more
of
Figure
EXAM
within
or
to:
because

a
mixture
pure

is
you
alloy
Pure
metal
Layers
slide
easily
means
,
can
ge t
the
Same
me ta
ls
back
agai
n
force
chem
ical
means
.
applied
Alloy
Figure
15.5.2
Alloys
as
Modifying
DID
YOU
modern
alloys
properties.
from
a
type
of
can
open
temperature
the
to
out
when
the
layers
cannot
slide
their
is
90 ºC
original
temperature
and
aluminium
alloys
is
ductile.
It
has
a
low
density
and
is
resistant
to
because
making
it
but
has
an
frames,
oxide
food
film
on
its
surface.
containers
and
So
cans,
it
is
used
especially
and
drinks
that
are
for
acidic.
go
form
drops.
window
the
when

Duralumin
alloy
magnesium
is
146
because
properties
aluminium
foods
back
metals
easily.
‘smart
for
alloy’
pure
easily
Springs
corrosion
made
than
less
have
Pure
‘memory’
stronger
slide
KNOW?
Aluminium
Some
are
Layers
much
(Al
and
stronger
with
silicon)
than
small
is
amounts
used
pure
for
of
making
aluminium
but
copper,
aircraft
still
has
manganese,
bodies.
a
low
The
alloy
density.

Aluminium
ships

Alloys
to
alloys
because
of
make
containing
they
have
aluminium
the
with
cylinder
10%
magnesium
improved
silicon
heads
for
resistance
(up
car
to
are
to
12%)
engines
used
for
corrosion
and
nickel
because
building
by
seawater
.
are
they
EXAM
used
do
Y
ou
expand
very
much
when
TIP
not
do
no t
heated.
remem
ber
Steel
of
alloys
in
Pure
iron
is
too
weak
to
be
useful.
The
iron
from
the
blast
furnace
have
the
parti
cular
differe
nt
brittle
to
be
used
for
constructing
bridges
and
buildings
it
contains
too
much
carbon.
Steel
is
an
alloy
of
iron
with
carbon
uses
carbon
and
other
metals.
There
are
several
types:
the

Mild
steel
(about
0.25%
carbon)
is
soft
and
malleable.
So
it
is
of
or
their
with
making
wires
buildings
where
for
and
foods
and
in
general
shaping
drinks,
is
engineering,
required.
where
it
is
It
is
covered
e.g.
also
car
used
with
tin
bodies
to
to
make
the
alloy
relat
ing
alloy
s
pro pe
rties
and
impr
oves
to
how
the
used
pro pe
rties
for
on
because
the
percen
tages
me ta
ls
alloy
s.
is
Conc
entra
te
too
to
of
the
and
me ta
l.
cans
prevent
it
from
rusting.

High
carbon
more

Low
as
steel
brittle.
alloy
It
steels
chromium,
strong
for
is
and
to
contain
and
low
0.5%
make
nickel
ductility
bicycle
and
tools
between
manganese,
have
bridges
(between
used
1%
chains,
and
and
and
1.4%
such
carbon)
as
5%
of
titanium.
malleability.
where
is
hammers
other
They
is
but
chisels.
metals
are
Nickel
strength
harder
and
such
hard
steels
required.
and
are
used
KEY
T
ungsten
1
steel
is
used
for
high-speed
tools
because
it
does
not
change
An
high
alloy
metallic
Stainless
steels
may
contain
up
to
20%
chromium
and
up
to
mixture,
of
within
two
They
are
strong
and
resist
corrosion.
So
they
are
used
metals
or
a
or
mixture
of
10%
one
nickel.
a
lattice,
temperatures.
more

is
shape
a
at
POINTS
for
or
more
metals
with
a
the
non-metal.
construction
of
industrial
chemical
vessels,
surgical
instruments
and
2
Alloys
are
used
instead
of
pure
cutlery.
metals
Lead
Lead
and
is
a
lead
very
alloys
soft
metal.
It
was
formerly
used
for
making
water
because
they
have
improved
properties
such
increased
hardness,
pipes
strength
because
it
is
very
malleable.
It
is
relatively
unreactive,
so
it
is
also
or
line
lead
the
nowadays
Solders
than
reaction
are
that
is
alloys
of
vessels
in
of
either
car
some
chemical
plants.
The
main
use
and
lead
tin.
3
or
The
pure
melting
tin.
point
Solders
of
have
solders
the
is
to
corrosion.
of
batteries.
lead
pure
in
increased
used
resistance
to
as
increased
Alloys
of
aluminium
increased
strength
increased
resistance
have
and
lower
following
to
uses:
corrosion.

Joining
metals.
Solder
is
easily
melted
and
has
a
good
adhesive
4
power
(it
sticks
metals
together
strongly).
Solder
containing
95%
Alloys
of
iron
increased
and
5%
lead
is
used
for
joining
components
of
electrical
For
joining
pipes
together
a
solder
containing
66%
lead,
32%
2%
antimony
is
resistance
Articles
made
Low
alloy
from
pieces
of
tin
are
joined
by
using
a
60%
lead
and
40%
steels
strength
are
is
used
required.
alloy
steels
are
used
tin.
where
both
resistance
Other
corrosion.
solder
High
containing
to
used.
where

have
hardness
tin
5
and
strength,
apparatus.
and

(steels)
tin
strength
to
and
corrosion
are
alloys
required.

Brass
(copper
and
zinc)
is
stronger
than
copper
but
is
relatively
6
malleable.

Bronze
So
it
is
So
it
(copper
used
for
is
used
and
for
tin)
moving
is
musical
harder
parts
of
instruments
than
either
machines,
and
copper
statues
Solders
are
and
which
alloys
of
lead
ornaments.
or
and
tin
alone.
tin
joining
are
used
for
metals.
bells.
147
15.6
Metals
and
the
environment
Corrosion
LEARNING
OUTCOMES
Corrosion
At
the
end
of
this
topic
surface.
should
be
able
is
Reactive
describe
needed
metals
and

the
for
greater
conditions
the
with
corrosion
reference
to
of
iron
metals
the
importance
and
the
faster
metal,
their
in
the
living
the
dissolving
such
metal,
a
freshly
a
thin
it
formed
they
of
rate
faster
as
away
of
a
magnesium
metal
and
inwards
iron
from
corrode
if
its
the
is
of
the
is
are
the
placed
corrosion.
rate
of
relatively
surface
are
environment
of
In
acidic.
in
general,
corrosion.
resistant
to
aluminium
For
which
reactive
the
the
more
Although
with
metals,
is
reactive
This
is
the
placed,
aluminium
corrosion.
reacts
metal
the
is
a
because
oxygen
to
form
of
oxide
layer.
This
oxide
layer
does
not
easily
flake
off
and
is
compounds
chemically
to
which
acidity
is
the
reactive
aluminium
explain
gradual
metals
to:
conditions

the
you
systems
and
unreactive.
Alkalis
also
corrode
some
metals.
the
environment

discuss
metals
the
harmful
and
their
effects
of
Rusting
compounds
Rusting
to
living
systems
and
is
a
special
form
of
corrosion
that
only
applies
to
iron
and
the
iron
alloys.
Rusting
only
occurs
when
both
water
and
oxygen
(from
environment.
the
air)
are
hydrated
present.
iron(III)
The
oxide
oxygen
and
air
react
with
the
iron
to
form
(rust):
1
2Fe(s)
+
1
O
2
EXAM
Rust
It
is
impo
rtant
distin
guis
h
co rros
ion
Rust
ing
that
fresh
a
flakes
iron
shows
an
of
the
ses
xH
3
O(s)
2
alka
line
off
the
surface
surface
is
of
exposed
iron
to
very
allow
easily.
When
further
it
fl akes
rusting.
off,
Figure
a
15.6.1
experiment
to
study
the
conditions
for
rusting.
Anhydrous
Boiled
water
and
air
calcium
(contains
ation
(contains
no
air)
chloride
dissolved
air)
of
iron
acidity
but
most
rustin
g
rapid
Gauze
of
unde
r
cond
ition
s.
Iron
nails
A
Figure
YOU
O
iron(
III)
as
increa
ses
DID
Fe
2
fo rm
Co rros
ion
is
→
Water
hydr
ated
iron
O(l)
2
rustin
g.
oxyg
en
and
increa
xH
react
ion
Moist
oxide.
+
you
be tw
een
and
is
invo
lving
water
(g)
2
TIP
B
15.6.1
Investigating
C
the
conditions
needed
D
for
rusting
KNOW?
2+
As
well
as
Fe
,
other
metal
In
ions
essential
for
life
bottles
from
copper(II)
for
ions
efficient
in
the
to
body,
are
respiration
manganese(II)
attached
which
ions
some
A
and
the
air
are
148
the
iron
present.
In
rusts
because
bottle
C
the
both
iron
water
does
and
not
oxygen
rust
because
needed
the
anhydrous
the
air.
calcium
chloride
removes
the
water
vapour
from
and
which
In
bottle
D
the
iron
does
not
rust
because
boiling
the
water
are
removes
all
the
water
which
air.
Rusting
is
dependent
on
the
pH
of
the
air
or
enzymes
which
in
the
iron
prevent
environment
unwanted
B,
include
oxidations.
is
alkaline.
is
placed.
Rusting
is
greater
if
the
pH
of
the
The
importance
of
metals
to
life
DID

Chlorophyll
is
an
essential
substance
for
plants
to
make
YOU
glucose
Carbon
by
photosynthesis.
The
chlorophyll
molecule
traps
the
energy
Sun.
Complex
energy
transfers
then
convert
the
energy
reactions
to
form
glucose.
At
the
at
bonding
molecule
is
a
magnesium
ion.
Without
centre
this
of
chlorophyll
will
not
absorb
sunlight
very
haem
Iron(II)
ions
are
haemoglobin
carries
important
in
oxygen
red
in
blood
around
the
the
cells.
well.
correct
than
body.
A
molecule
is
is
oxygen.
toxic
Carbon
because
the
oxygen
it
bonded
to
2+
functioning
Haemoglobin
ions
magnesium
Fe

times
Fe
the
replaces
ion,
200
to
via
monoxide
chlorophyll
is
2+
in
oxidation–reduction
monoxide
from
better
the
KNOW?
a
of
So
haemoglobin
oxygen-carrying
protein
called
.
haem
that
is
cells
attached
you
are
starved
loses
function.
of
its
Body
oxygen
and
die.
2+
to
the
protein.
At
the
centre
of
the
haem
molecule
is
an
Fe
ion
2+
bonded
to
four
haemoglobin
nitrogen
carries
atoms.
oxygen
Oxygen
around
bonds
the
body
to
to
the
the
Fe
ion.
tissues
The
where
Plankton
it
is
needed
for
respiration.
(microscopic
in

Zinc
ions
are
bonded
to
an
enzyme
(carbonic
anhydrase)
present
the
organisms
sea)
in
Increasing
red
blood
cells.
The
enzyme
catalyses
the
removal
of
carbon
dioxide
concentratio
Shrimps
from
than
part
the
it
blood.
would
in
the
It
be
way
makes
the
without
the
reaction
the
reaction
about
enzyme.
The
a
million
zinc
ions
times
play
a
faster
critical
of
mercur y
in
organism
Fish
works.
Man
T
oxic
metals
Figure
Many
metals
and
metal
compounds
harm
living
things
if
they
15.6.2
The
concentration
mercury
from

factories
or
Compounds
of
are
lead
combustion
of
The
gases
exhaust
dumped
the
were
fuel.
by
formerly
Very
from
humans.
few
vehicles
For
added
fuels
using
to
now
this
example:
petrol
to
contain
fuel
food
improve
lead
contain
and
Lead
compounds
are
still
used
in
some
paints
in
KEY
of
paints
the
or
world.
batteries
Lead
are
is
also
not
used
disposed
in
of
some
car
correctly,
batteries.
lead
may
If
Corrosion
or
air
.
Lead
compounds
are
poisonous.
system,
including
the
brain,
especially
in
young
Arsenic
compounds
are
poisonous.
They
can
get
into
Rusting
is
with
the
mining
waste
and
from
disposal
of
some
The
starter
batteries
If
of
many
disposed
of
cars
contain
incorrectly,
electrical
cadmium
poisonous
Aluminium
forms
layer
the
Mercury
fish
poison
and
nickel
cadmium
can
Chlorophyll
contains
get
can
be
and
spilled
Mercury
it
can
humans
from
and
broken
its
accumulate
(Figure
thermometers
compounds
in
the
food
are
in
hospitals
particularly
chain
and
poisonous
5
The
red
eventually
The
15.6.2).
of
metals
incorrectly
may
cause
Metals
may
react
with
water
and/or
for
haem
compounds
that
are
poisonous.
air
These
iron
for
Rust
from
enter
iron
haemoglobin
cells
bonds
contains
to
in
iron.
oxygen
respiration.
and
corrode
to
form
Compounds
diffuse
into
the
soil
of
lead,
arsenic,
soluble
and
mercury
are
and
poisonous
eventually
photosynthesis.
in
blood
cadmium

is
problems:
6

which
and
used
Disposal
on
groundwater.
laboratories.
to
oxide
surface.
essential

an
of
components.
magnesium,
into
of
oxygen.
groundwater
4
electrodes.
and
children.
its

reaction
water
unreactive
from
of
the
3

dissolving
into
harm
iron
nervous
the
surfaces.
these
get
They
is
some
2
groundwater
a
chain.
POINTS
metal
parts
along
lead
1
compounds.
increases
the
compounds.
lead
of
escape
to
animals.
rivers.
may
form
unsightly
pools
of
waste
that
reduce
plant
growth.

Waste
from
flammable
aluminium
extraction
may
react
with
water
and
form
gases.
149
16
Non-metals
16.1
Properties
of
some
non-metals
Physical
LEARNING
Many
At
the
end
of
this
topic
be
able
a
non-metals
liquid.
describe
the
physical
The
are
gases
physical
at
r.t.p.
properties
but
of
others
are
non-metals
solids
are
and
largely
bromine
the
properties
to
those
of
metals.
and
Most
chemical
non-metals
to:
opposite

of
you
is
should
properties
OUTCOMES
of
non-metals:
some

non-metals
do
not
conduct
electricity.
An
exception
is
carbon
in
the
form
of
graphite.

describe
the
non-metals
reaction
with
of
some
oxygen
and
metals

describe
the
reducing
oxidising
properties

do

are
some

non-metals.
The
have
have
have

are
a
soft
T
able
and
in
16.1.1
T
able
16.1.1
Element
Figure
16.1.1
Some
so
the
are
are
form
in
easily
of
at
the
at
carbon
So
they
with
boiling
appear
density
compares
Physical
and
gases
when
may
form.
is
non-metals
points
lower
exception
solid
are
Many
however,
An
the
surface
much
carbon
in
melting
dull
metals,

when
metals.
a
heat.
exceptions
low
most

conduct
brittle
hit.
and
of
not
in
the
break
giant
points
in
form
apart
of
graphite.
easily
when
structures.
comparison
with
r.t.p.
solid
shiny,
r
.t.p.
form.
e.g.
in
scratched
Crystalline
carbon
as
comparison
with
a
of
non-
diamond.
with
knife.
forms
An
most
metals.
exception
is
diamond.
some
physical
properties
Melting
of
some
properties
of
selected
non-metals.
non-metals
Melting
Density
at
Appearance
non-metallic
–3
elements:
sulfur,
phosphorus,
point
bromine,
carbon
(ºC)
point
(ºC)
r.t.p.
(g cm
)
and
Hydrogen
−259
−253
+3550
+4827
0.000083
Colourless
3.51
Colourless
gas
iodine
Carbon
(diamond)
EXAM
If
you
TIP
are
describ
e
between
meta
ls,
asked
the
is
differe
nces
and
best
in
Nitrogen
−210
−196
0.00116
Colourless
gas
Oxygen
−218
−183
0.00133
Colourless
gas
Sulfur
+119
+445
1.96
Yellow
Chlorine
−101
−35
0.00296
Green
to
differe
nce
meta
ls
it
to
non -
therm
al
mallea
bility
brittlen
ess)
at
r
.t.p.
excep
tions
select
to
properties
(as
Reaction
oppose
d
if
you
of
non-metals
dens
ity
are
fewer
the
gene
ral
with
oxygen
to
Many
non-metals
oxygen)
to
form
burn
in
oxides.
2H
rules
(g)
+
excess
For
O
2
choose
oxygen
or
example:
(g)
→
2H
2
O(l)
2
these
.
S(s)
+
O
(g)
→
2
C(s)
+
O
(g)
2
150
gas
cond
uctiv
ity,
and
T
here
solid
electr
ical
Chemical
and
solid
SO
(g)
2
→
CO
(g)
2
in
air
(which
is
21%
Nitrogen
react
at
does
high
Chlorine
not
does
Reaction
combine
temperatures
not
with
react
with
non-metals
react
when
heated.
example:
Sodium
oxygen
in
the
at
r.t.p.
presence
although
of
an
it
will
electric
spark.
oxygen.
metals
Some

with
and
For
burns
in
with
metals
high
in
the
electrochemical
series
DID
chlorine
to
form
sodium
The
chloride:
is
2Na(s)
+
Cl
(g)
→
YOU
old
KNOW?
name
‘azote’
for
which
nitrogen
means
2NaCl(s)
2
‘unreactive’.
Other
halogens
react
in
a
similar
is

Magnesium
burns
in
oxygen
to
Although
form
magnesium
not
be
oxide:
very
made
reactive,
to
react
temperatures.
2Mg(s)
+
O
(g)
nitrogen
way.
→
it
at
For
can
high
example,
2MgO(s)
2
metals

When
heated,
iron
combines
with
molten
sulfur
to
form
iron( II)
ionic
sulfide:
when
Fe(s)

When
with
heated,
+
reactive
hydrogen
to
S(l)
metals
form
2Na(s)
+
→
metal
H
(g)
as
Groups
I
heated
in
and
II
called
form
nitrides
nitrogen.
For
example:
FeS(s)
such
in
compounds
sodium
and
aluminium
react
3Ca(s)
+
N
(g)
→
Ca
2
N
3
(s)
2
hydrides:
→
2NaH(s)
2
Oxidising

and
Hydrogen
hydrogen
series
to
is
reducing
a
good
reduces
the
properties
reducing
metal
metal.
PbO(s)
For
+
agent.
oxides
At
below
high
zinc
suitable
catalyst)
H
(g)
N
(g)
→
3H
2

Carbon
is
reduces
metal.
also
Pb(s)
+
H
For
good
oxides
O(g)
temperature,
nitrogen
(g)
to
2NH
2
a
metal
(high
reduces
+
electrochemical
2
conditions
hydrogen
the
example:
2
Under
temperatures,
in
pressure
and
a
ammonia:
(g)
3
reducing
below
agent.
At
aluminium
high
in
the
temperatures,
reactivity
series
it
to
KEY
POINTS
the
1
example:
Most
non-metals
conduct
ZnO(s)
+
C(s)
→
Zn(s)
+
Oxygen
oxides
is
a
and
good
some
oxidising
agent,
non-metals
to
oxidising
non-metal
most
metals
oxides.
For
to
metal
+
O
(g)
→
2MgO(s)
melting
→
P
2
4P(s)
+
5O
brittle
Most
2
O
4
and
have
boiling
non-metals
lower
(g)
and
heat,
low
points.
example:
2
2Mg(s)
not
or
CO(g)
are

do
electricity
have
(s)
density
a
dull
have
than
surface
a
metals,
and
are
10
soft.

Chlorine
is
solution.
a
For
good
oxidising
example,
it
agent,
either
as
a
gas
or
as
an
aqueous
3
oxidises:
Many
non-metals
oxygen
–
hydrogen
to
hydrogen
(g)
+
Cl
2
form
react
oxides
with
and
chloride:
with
H
to
(g)
→
metals
to
form
metal
2HCl(g)
2
compounds.
–
ammonia
to
nitrogen:
4
2NH
(g)
+
3Cl
3
–
aqueous
(g)
→
2
bromides
to
N
(g)
+
good
2
aqueous
+
Cl
(aq)
2
→
and
carbon
are
reducing
agents.
bromine:
5
2KBr(aq)
Hydrogen
6HCl(g)
2KCl(aq)
+
Br
(aq)
Oxygen
good
and
chlorine
oxidising
are
agents.
2
151
16.2
The
of
preparation
gases
Preparation
LEARNING
When
At
the
should

end
be
describe
of
this
able
the
topic
to:
we
prepare

whether

how
of
some
introduction
method
to
gas
in
the
laboratory,
we
need
to
consider:
the
gas
collect
is
the
soluble
gas.
or
This
insoluble
depends
in
on
water.
of
it
is
denser
or
less
dense
than
the
air
density
(see
of
Figure
the
gas:
16.2.1).
how
to
dry
the
gas
to
free
it
from
water
vapour.
In
selecting
a
of
drying
collection
a
gases

the
an
laboratory
preparation
relate
gases:
you
whether

of
OUTCOMES
gases
to
agent,
we
need
also
to
consider
whether
the
gas
itself
reacts
their
with
the
drying
agent.
properties.
Preparation
Carbon
a
marble
Air
Carbon
of
dioxide
chips
carbon
is
dioxide
prepared
(calcium
by
dropping
carbonate)
dilute
(Figure
hydrochloric
acid
onto
16.2.2).
dioxide
Hydrochloric
Gas
acid
jar
U-tube
Gas
jar
b
Carbon
Marble
chips
dioxide
Anhydrous
calcium
chloride
Upside-down
gas
Figure
jar
In

this
16.2.2
Preparation
of
carbon
dioxide
preparation:
Carbon
dioxide
upward
denser
displacement
than
of
air.
So
it
is
collected
in
the
gas
jar
by
air.
Hydrogen

Carbon
dioxide
is
soluble
in
water,
so
it
is
preferable
not
to
collect
Air
over
Figure
16.2.1
a
Carbon
than
air,
dioxide
so
upward
is
is
denser
collected
by

The
water.
carbon
some
air.
b
Hydrogen
dense
than
by
it.
This
the
arises
reaction
from
the
flask
water
will
in
have
acid.
The
carbon
dioxide
can
be
the
passed
air,
so
calcium
chloride
in
a
U-tube
to
dry
it.
(Calcium
of
over
air.
oxide,
is
drying
agent,
cannot
be
used
because
moist
carbon
downward
displacement
152
in
from
is
another
collected
vapour
hydrochloric
anhydrous
less
coming
displacement
dilute
of
water
dioxide
dioxide
is
acidic
and
reacts
with
the
basic
calcium
oxide.)
it
Preparation
of
Concentrated
oxygen
hydrogen
peroxide
is
dropped
slowly
from
a
dropping
Hydrogen
funnel
into
a
flask
containing
manganese( IV)
oxide
catalyst.
peroxide
2H
O
2
(aq)
→
O
2
(g)
+
2H
2
O(l)
2
Oxygen
In
this
preparation:
Manganese (IV)
oxide

The
oxygen
is
collected
in
the
gas
jar
by
downward
displacement
of
Water
water

(Figure
Oxygen
is
16.2.3).
only
produced
will
slightly
be
soluble
collected
in
in
water,
the
gas
so
most
of
the
oxygen
jar.
Figure

The
oxygen
in
the
gas
jar
will
contain
some
water
vapour
16.2.3
Preparation
by
because
hydrogen
it
is
collected
passed
over
Preparation
Ammonia
can
be
paste
of
of
water.
an
alkaline
by

calcium
Ammonia
Ammonia
The
an
+
is
gas
hydroxide
Ca(OH)
that
is
any
and
(aq)
a
dry,
it
can
be
U-tube.
very
alkali
soluble
with
ammonium
in
any
water.
Ammonia
ammonium
chloride
→
2NH
(g)
+
CaCl
3
less
dried
dense
than
displacement
is
soluble
aqueous
ammonia
chloride
be
required
in
is
salt.
heated
A
gently
(aq)
+
2H
2
O(l)
2
preparation:
using

is
chloride
2
downward

oxygen
of
peroxide
16.2.4).
Cl(aq)
this
the
warming
4
In
If
calcium
oxygen
ammonia
prepared
(Figure
2NH
is
over
anhydrous
of
decomposition
is
cannot
with
in
of
water,
solution
passed
be
air.
so
of
over
used
So
it
an
is
collected
in
the
gas
jar
by
is
preferable
not
to
prepare
it
alkali.
calcium
because
concentrated
it
air.
oxide
to
ammonia
sulfuric
acid
dry
it.
reacts
because
Calcium
with
the
it.
acid
It
cannot
reacts
Calcium
hydroxide
ammonium
+
chloride
Ammonia
with
ammonia
(neutralisation
reaction).
Gas
KEY
jar
POINTS
Heat
1
Gases
that
are
denser
than
air
are
collected
by
upward
Calcium
displacement
collected
2
Calcium
drying
with
3
air.
chloride
these
or
or
that
are
less
displacement
concentrated
carbon
dioxide
dense
of
than
air
Wire
air.
sulfuric
acid
can
because
they
do
be
not
oxide
are
used
gauze
for
react
Figure
16.2.4
Preparation
of
ammonia
gases.
oxide
with
Gases
downward
oxygen
Calcium
react
by
of
is
used
for
drying
ammonia
because
it
does
not
ammonia.
153
16.3
Uses
of
their
Uses
LEARNING
At
the
should
end
be
of
this
able
describe
based
the
on
list
the
compounds
some
gases
topic
Carbon
you
dioxide
to:
uses
their
of
Some
or
gases
fire
uses
of
some
extinguishers
produce
Carbon
properties
carbon
dioxide
oxygen

and
OUTCOMES


of
non-metals
from
is
contain
dioxide
denser
reaching
when
than
it.
carbon
sprayed
air
Carbon
dioxide
and
on
gas
the
fire
‘blankets’
dioxide
under
the
(see
fire,
extinguishers
pressure
7.4).
preventing
are
especially
non-
useful
for
dealing
with
fires
involving
fl ammable
liquids
and
metals.
electrical

The
the
equipment.
‘fizz’
in
drink
fi zzy
under
drinks
is
made
by
pumping
carbon
dioxide
into
pressure.
Oxygen

We
need
place
in
a
improve
Oxygen
is
welding
the
the
poisoning

constant
all
cells
supply
of
our
respiration
and
heart
used
torch,
in
of
of
oxygen
body.
patients
with
16.3.1
Oxygen
is
used
in
torch
to
cut
poor
in
which
takes
hospitals
blood
flow,
to
blood
welding
acetylene
(joining)
(ethyne,
metals.
C
H
)
In
burns
an
in
oxyacetylene
oxygen.
is
produced,
which
is
capable
A
very
hot
2
of
melting
most
metals.
join

or
used
the
flame
oxyacetylene
respiration,
is
disease.
2
Figure
for
Oxygen
A
major
use
of
oxygen
is
in
steel
production.
A
blast
of
oxygen
is
metals.
blown
through
impurities
Uses
of
in
the
the
molten
iron
some
and
iron.
the
The
oxygen
impurities
non-metals
and
are
oxidises
then
their
many
of
the
removed.
compounds
Carbon

EXAM
Carbon
in
the
form
of
diamond
is
used
in
jewellery
because
of
its
TIP
lustre.
Y
ou
lo ts
do
no t

have
Diamond
is
used
in
drill
tips
for
high-speed
drills
because
of
its
know
hardness.
of
uses
non -m
e tal.
gene
rally
fo r
uses
on

Graphite

Carbon
is
used
in
pencil
‘leads’
and
as
electrodes.
will
suffi
cient
.
men
tione
d
sylla
bus.
each
Two
be
Conc
entra
te
uses
to
those
fibres
where
are
used
extra
to
strengthen
strength
is
some
required,
types
of
plastic,
parts
of
pumps.
e.g.
especially
those
in
the
Sulfur

The
major
use
of
sulfur
is
for
the
industrial
production
of
sulfuric
acid.

Sulfur
is
harder.

154
Sulfur
used
This
in
is
powder
the
called
is
manufacture
of
tyres
to
make
the
rubber
vulcanisation.
used
as
a
fungicide
on
plant
materials.
Phosphorus
Nitrogen

The
main
use
of
phosphorus
is
in
the
production
of
Hydrogen
phosphate
fertilisers.

Phosphorus
sulfide
is
used
to
make
the
heads
of
‘strike
anywhere’
Ammonia
matches.
A
violet
allotrope
of
phosphorus
is
used
to
make
the
(NH
on

A
the
box
small
of
safety
amount
of
Nitric
acid
Ammonium
strip
3
)
(HNO
3
)
nitrate
matches.
phosphorus
is
used
to
make
the
alloy,
phosphor-
bronze.
Phosphoric
NPK
Chlorine
acid

Chlorine
many

The
is
used
to
make
sodium
hypochlorite,
which
is
present
in
bleaches.
active
fertiliser
Sulfuric
ingredients
of
some
insecticides
are
Phosphate
chlorine-containing
acid
rock
Potassium
chloride
compounds.

Chlorine
is
used
to
sterilise
swimming
pools
and
in
water
treatment.
Figure
16.3.2
Flow
NPK

A
major

Some
use
dry
of
cleaning
compounds
because
chlorine
of
they
is
and
make
industrial
chlorine.
are
to
Many
harmful
to
monomer
solvents
of
the
the
these
and
are
ozone
for
plastic,
refrigerants
being
layer
the
(see
The
use
soil
by
of
nitrogen
farmers
to
is
to
make
increase
fertilisers.
the
yield
of
an
contain
16.4).
KEY
major
the
making
withdrawn
Fertilisers
are
their
crops.
POINTS
spread
1
on
for
PVC.
Nitrogen

chart
fertiliser
Carbon
dioxide
is
used
in
fire
Fertilisers
extinguishers.
provide
some
nitrogen
are
(N),
called
with
of
the
essential
phosphorus
NPK
fertilisers.
hydrogen
at
(P)
elements
and
When
450 ºC
and
needed
potassium
nitrogen
200
for
(K).
from
the
atmospheres
plant
So
growth:
these
air
fertilisers
2
combines
pressure,
in
of
a
catalyst,
ammonia,
NH
,
is
formed.
The
ammonia
NPK
reacted
with
fertilisers
nitric
(Figure
acid
and
phosphates
are
added
to
welding.
Carbon
Nitrogen
being
is
used
oxidised,
as
in
hospitals
in
the
form
is
used
of
for
jewellery.
Carbon
make
in
the
form
16.3.2).
an
and
used
diamond
of

for
is
3
then
is
and
the
3
presence
Oxygen
as
inert
a
atmosphere
to
prevent
substances
graphite
‘leads’
and
is
used
as
in
pencil
electrodes.
coolant.
4
Sulfur
is
used
manufacture
in
of
the
tyres.
Silicon
5

Silicon
in
highly
purified
form
is
used
for
making
silicon
chips
Phosphorus
is
used
on
for
matchboxes
and
is
present
in
computers.
NPK

Sand
lime
contains
(calcium
silicon( IV)
oxide)
oxide.
and
Glass
sodium
is
made
by
heating
sand
fertilisers.
with
6
carbonate.
Chlorine
is
bleaches

Glass
fibres
are
silicates
(compounds
of
silicon
and
oxygen).
used
and
in
to
make
water
Glass
treatment.
fibres
can
a
density
low
tanks,

be
used
and
roofing
Silicates
to
is
and
strengthen
strong.
boat
containing
So
it
plastics
is
used
(fi breglass).
to
make
Fibreglass
pipes,
has
storage
7
hulls.
e.g.
traces
of
is
used
Clay
contains
ceramics
pottery,
are
make
transition
element
atoms
are
used
for
Silicates
are
used
for
emeralds.
strengthening

to
fertilisers.
8
jewellery,
Nitrogen
a
variety
formed.
stoneware
of
silicate
Examples
and
minerals.
of
porcelain.
When
ceramics
are
clay
is
baked,
earthenware
ceramics
and
containing
element
plastics,
glass.
in
Silicates
transition
atoms
are
used
in
jewellery.
155
16.4
Harmful
effects
non-metal
of
compounds
Pollution
LEARNING
OUTCOMES
Pollution
At
the
end
of
this
topic
the
should
be
able
natural
describe
of
the
harmful
non-metals
and

the
the
and
on
the
an
unfavourable
effect
of
of
Sulfur
dioxide
solid

Fuels
such

When
plastics.

EXAM
The
as
effect
on
specific
coal,
burnt,
sulfur
introduced
into
generally
the
environment.
pollutants
petroleum
The
sulfur
is
and
convert
dioxide
oxidised
natural
gas
contain
some
and
of
sulfur
to
sulfur
dioxide.
sulfur.
the
sulfur
dioxide
trioxide
react
Reactions
to
with
sulfur
water
in
the
trioxide.
in
the
air
to
acids.
acid
falls
to
the
ground
dissolved
in
the
rainwater.
This
is
called
TIP
acid
When
you
that
refere
nce
revis
e,
you
you
info rm
ation
carbon
mak
e
cross-
o ther
Rain
is

Acid
described
rain
causes
decrease
in
(limestone,
For
can
rain.

section
s
sylla
bus.
exam
ple,
Hydrogen
mon
oxide
in
13.1

Hydrogen
of
fertility,
marble)
if
trees
has
and
erosion
and
it
of
a
pH
some
lower
aquatic
buildings
corrosion
of
metal
than
5.6.
organisms,
made
of
carbonate
structures
such
as
rocks
bridges.
KNOW?
under
(see
can
H
S,
is

of
anaerobic
13.1).
coke
Hydrogen
Oxides
pesticides
sulfide,
formed
from
the
breakdown
of
organic
2
matter

and
death
rain
sulfide
industrial
Herbicides
acid
find
15.6
.
YOU
soil
as
abou
t
digesters
DID
are
Pollutants
waste,
form
and
materials
water).
raised

the
or
systems
atmosphere
of
air
their
living
problems
disposal
particularly
sure
(earth,
environment
describe
by
contaminating
effects
The
compounds
when
environment
to:
have

occurs
you
It
conditions,
is
also
e.g.
formed
in
swamps
during
and
petroleum
in
biogas
refining
and
ovens.
sulfide
is
poisonous
to
humans
and
animals.
nitrogen
Nitrogen
oxides
(NO
and
NO
)
are
formed
by
the
combination
of
2
accumulate
animals.
in
They
fatty
get
tissues
more
of
nitrogen

more
concentrated
up
and
the
Nitrogen(II)
.
The
oxide,
NO
2
They
can
adversely
reproduction
of
In
and
can
presence
in
petrol
and
diesel
engines.
NO,
can
dissolve
be
in
further
rain
to
oxidised
form
in
acid
the
atmosphere
to
rain.
of
hydrocarbons
from
car
exhausts,
ozone
and
marine
nitrogen
oxides
react
to
form
photochemical
smog
birds.
which

contains
Nitrogen
and

The
more
Carbon
Much
is
of
can
other
harmful
dioxide
Energy
many
dioxide
eyes.
even
156
temperatures
2
the
sunlight,
mammals
high
affect

the
at
food
NO
chain.
oxygen
and
harm
chemicals.
the
lungs
compounds
irritants
and
emitted
this
harmful
present
can
irritate
in
cause
the
nose,
photochemical
throat
smog
are
asthma.
methane
from
infrared
and
and
the
surface
radiation
is
of
the
trapped
Earth
by
as
infrared
gases
in
the
radiation.
atmosphere.

Carbon
dioxide
is
formed
when
fuels
are
burnt.
Methane
is
formed
DID
as
a
result
digestive
of
bacterial
systems
of
action
in
swamps,
rice
paddy
fields
and
Dumped
animals.
to

Carbon
good
dioxide
and
absorbers
radiation
by
of
methane
infrared
greenhouse
are
greenhouse
radiation.
gases
leads
The
to
gases.
absorption
the
heating
They
of
of
This
is
called
global
An
increase
in
the
concentration
plastics
the
atmosphere
due
to
may
get
nets
or
trapped
die
agriculture
absorbed
by
the
in
of
carbon
dioxide
and
The
atmosphere
plastic
plastic
the
gullet.
gets
Biodegradable
may
break
industrialisation
more
infrared
and
radiation
down
into
methane
particles
which
are
more
to
aquatic
life.
being
atmosphere.
DID

in
when
warming
increased
results
danger
birds
the
harmful
intensive
a
or
infrared
microscopic
in
are
Animals
are
plastics

KNOW?
wildlife.
into
atmosphere.
YOU
the
heats
up
more
than
usual.
Global
warming
YOU
KNOW?
is
increased.
Incineration

The
effects
polar
ice
of
increased
caps,
unpredictable
the
causing
global
a
weather,
temperature
of
rise
warming
in
sea
formation
the
oceans,
include
levels,
of
more
more
leading
melting
violent
deserts
to
the
the
may
and
and
death
of
of
corals.
waste
materials
poisonous
particulates
increasing
of
cause
to
Incineration
poisonous
get
may
gases
into
also
the
and
air.
produce
substances
called
dioxins.
Chlorofluorocarbons

High
in
the
(CFCs)
atmosphere
is
a
and
layer
the
of
ozone
ozone
layer
which
reduces
the
KEY
amount
of
ultraviolet
radiation
reaching
the
1

The
CFCs
formerly
used
as
refrigerants
and
POINTS
Earth.
in
aerosol
Sulfur
dioxide
burning
catalyse
the
breakdown
of
ozone
into
The
breakdown
ozone
layer
.
So
of
ozone
more
results
ultraviolet
in
the
fossil
formation
radiation
reaches
of
holes
the
in
This
results
and
reduced
in
increased
rain.
Earth’s
surface.
2
Nitrogen
risk
of
getting
skin
cancer,
eye
oxides
to
some
cause
and
leading
and
to

Nitrates
phosphates
cause
eutrophication
in
Nitrates
and
they

cover
Water
Carbon
monoxide
eutrophication.
The
The
and
phosphates
surface
feed
bacteria
fertilisers
get
cause
of
including
bacteria
aerobic
animals
from
groundwater
the
processes
the
use
the
up
lakes
excessive
and
on
fields
may
The
of
algae
so
that
5
die
because
plant
the
Increase
of
of
remains.
oxygen
in
lack
The
the
of
sunlight.
bacteria
water,
so
aquatic
6
in
carbon
CFCs
of
and
pollution
from
non-metals
is
from
glass,
ozone,
paper
7
plastics.
Broken
can
cause
injury
to
animals.
It
can
also
cause
fires
is
a
concentration
in
the
the
global
breakdown
leading
to
incidence
and
excessive
glass
It
increases
of
skin
cataracts.
Eutrophication
and

the
dioxide
catalyse
cancer
of
absorbs
warming.
multiply.
die.
sources
toxic
gas.
atmosphere
waste
main
and
are
radiation.
greenhouse
rivers.
growth
dioxide
infrared
water.
algae,
on
into
spread
Carbon
increased
Solid
sulfide
are:
phosphates
plants,
Aerobic

and
dissolve
and
gases.
4

rain
smog.
phosphates
hydrogen
Nitrates
acid
car
diseases.
3
Nitrates
from
cataracts
photochemical
resistance
from
causes
the
exhausts

fuels
oxygen.
acid

arising
sprays,
is
caused
amounts
phosphates
in
of
by
nitrates
lakes
and
by
rivers.
acting

as
Printing
a
lens,
inks
elements
from
such
compounds
focusing
as
from
paper
Sun’s
dumped
arsenic
paper
the
and
are
rays
in
the
cadmium.
also
on
flammable
ground
may
Bleaches
harmful.
material.
contain
and
toxic
chlorine
8
Plastic
to
in
waste
animals
their
may
by
lungs
cause
getting
or
harm
trapped
gullet.
157
17
Water
17.1
Properties
The
LEARNING
water
the
end
of
this
topic
be
molecule
able
is
a
small
molecule.
It
is
a
polar
molecule.
Polar
molecules
you
have
should
water
OUTCOMES
Water
At
of
a
partial
positive
charge
on
one
end
of
their
molecule
and
to:
a
partial
negative
charge
on
the
other.
These
partial
charges
are
+

relate
the
unique
properties
shown
by
the
symbols
δ
and
δ
(Figure
17.1.1).
Solvents
that
are
+
of
water
living
to
its
functions
in
not
charged
same)
systems
are
molecules

describe
how
the
water
where
called
are
the
centre
non-polar.
stronger
than
The
the
of
partial
charges
intermolecular
intermolecular
δ
and
forces
forces
δ
is
between
between
the
polar
non-
density
polar
of
(or
changes
molecules
of
a
similar
size.
with
temperature

explain
the
capacity
high
and
specific
low
heat
volatility
The
density
of
water
at
different
temperatures
of
For
most
liquids,
the
density
increases
as
the
temperature
decreases.
water
The

describe
the
properties
solvent
of
a
water.
density
higher
are
more
decrease
density
continues
density
than
closely
and
increase
packed.
when
(Figure
to
the
it
as
the
liquid
corresponding
Water
freezes
17.1.2(a)).
So
is
at
unusual:
0 ºC,
ice
at
there
floats
freezes.
liquid
in
is
4 ºC
a
The
because
its
the
solid
density
sudden
has
molecules
starts
decrease
to
in
water.
δ
O
−
−
a
H
b
H
δ+
δ+
Water
17.1.1
Water
is
a
polar
molecule.
1–
)
Figure
mc g(
H
H
Ice
O
O
+
water
H
H
H
ytisneD
Highest
O
O
O
density
Intermolecular
Ice
forces
H
H
O
O
O
H
O
O
H
–4
0
4
8
H
12
Temperature ( ° C)
Figure
17.1.2
a
The
of
DID
YOU
of
water
at
different
temperatures,
b
the
structure
KNOW?
Ice
The
density
ice
relatively
strong
intermolecular
is
less
structure
forces
between
than
in
dense
than
(Figure
the
water
17.1.2(b))
liquid.
When
because
that
ice
it
has
allows
melts,
this
a
the
relatively
molecules
structure
open
to
begins
cage-like
be
to
further
apart
collapse.
+
the
δ
the
δ
hydrogen
atoms
and
In
−
oxygen
atom
in
freezing
important
are
called
hydrogen
bonds.
of
a
hydrogen
about
a
covalent
water
third
bonds,
below
considerable
that
e.g.
4 ºC
of
still
in
fact
of
that
fish
ice
and
is
less
other
dense
than
aquatic
water
is
organisms.
The
remains
to
food
below
from
the
the
ice
river
so
or
that
lake
the
aquatic
organisms
still
bed.
has
of
Liquid
a
Other
properties
of
water
‘ice-like’
has
a
higher
specific
heat
capacity
and
boiling
point
than
it.
most
158
water
access
Water
structure
the
survival
some
F − F
.
amount
the
bond
have
is
for
The
denser
strength
weather,
water
other
molecules
of
comparable
molar
mass.
For
example,
the
boiling
point
of
water
(M
=
18)
is
+100 ºC
whereas
the
boiling
point
r
of
methane
(M
=
16)
is
−164 ºC.
Water
is
not
as
volatile
as
many
r
organic
solvents
properties
can
be
intermolecular
with
of
the
molar
Water
as
Water
a
is
a
its
explained
by
between
relatively
the
the
intermolecular
high
presence
polar
forces
boiling
of
the
water
point.
relatively
molecules
between
These
strong
compared
non-polar
molecules
mass.
solvent
good
nature
of
forces
weaker
similar
polar
because
of
solvent
water
in
everyday
allows
it
to
life
as
dissolve
well
as
both
in
industry.
ionic
The
compounds
as
Figure
well
as
polar
covalent
molecules.
Figure
17.1.4
shows
the
process
17.1.3
This
insect
on
dissolving.
the
water
a
b
skate
surface
of
because
high
due
a
can
of
surface
to
its
H
−
has
tension
relative
intermolecular
c
the
water
strong
forces.
H
−
O
Bond
strengthens
H
H
−
−
DID
−
O
O
−
−
−
a
O
specific
heat
substance
is
capacity
the
of
amount
H
H
−
O
The
−
H
H
KNOW?
H
H
O
YOU
−
H
O
O
H
−
−
H
−
−
H
of
−
H
H
heat
raise
energy
the
required
temperature
to
of
1 g
Bond
of
a
substance
by
1 ºC.
The
weakens
specific
heat
capacity
of
water
–1
is
Figure
17.1.4
a
Water
molecules
weaken.
c
Water
bond
to
the
molecules
ions.
surround
b
The
the
forces
ions
to
between
keep
the
them
in
relatively
high
(4.17 J g
solution.
whereas
such
as
CCl
it
for
non-polar
living
is
essential
things
take
to
life
place
because
in
many
aqueous
of
the
solution.
chemical
Many
of
reactions
the
in
tetrachloromethane
,
our
bodies
contain
polar
groups
such
as
− OH,
ions
derived
from
these,
e.g.
COO
.
Water
is
− COOH
essential
and
so
that
in
can
nerve
dissolve
and
conduction.
react.
The
layer
Dissolved
of
water
ions
play
around
an
ions
things
extremes
of
part
in
allowing
some
ions
to
pass
through
preventing
others
from
passing.
In
addition,
water
the
water
hydrolysis
reactions
in
the
plays
a
2
Ice
all
to
living
survive
it
takes
a
relatively
large
of
energy
to
change
the
body.
is
is
a
less
polar
of
water
.
Water
dense
has
its
than
Mak
e
water.
maximum
density
at
has
a
higher
specific
heat
capacity
and
boiling
point
volatility
than
most
other
the
molecules
of
in
mass.
5
Water
is
6
The
a
good
solvent
solvent
properties
for
of
ionic
water
and
are
polar
covalent
essential
you
supp
ortin
g
of
life
well
as
its
unus
ual
comparable
phys
ical
molar
that
impo
rtanc
e
and
as
lower
sure
4 ºC.
water
Water
TIP
molecule.
know
a
in
them
part
EXAM
Water
4
The
capacity
POINTS
1
3
present
helps
temperature
KEY
thermal
membranes
amount
in
survive
an
because
while
).
important
plays
cell
cannot
temperature.
specific
organisms
important
–1
ºC
these
of
part
(0.84 J g
− NH
high
compounds
low
compounds
2
or
is
4
Living
in
)
solvents
–1
Water
–1
ºC
ions
to
pro pe
rties.
compounds.
life.
159
17.2
Leaching,
and
hard
water
water
treatment
Leaching
LEARNING
OUTCOMES
Dissolved
At
the
end
of
this
topic
the
should
be
able
describe
of
the
water
and

the
properties
terms
hardness
describe
the
between
of
of
most
called
of
rivers.
water
describe
the
the
and
It
Hard
methods
can
in
as
is
lakes
and
rivers
surrounded
constantly
pollutants
Leaching
play
a
moving
get
plays
transferring
also
and
soft
rainwater
such
of
water
by
as
layer
through
of
water.
an
in
out
important
from
making
of
part
the
water
the
the
soil
in
soil
and
soil.
useful
This
is
removing
into
lakes
soil
and
hard.
containing
limestone,
it
dissolved
reacts
carbon
with
the
dioxide
calcium
moves
or
through
magnesium
and
magnesium
hydrogencarbonates
2+
in
water.
The
are
formed
2+
Ca
and
Mg
ions
cause
water
to
be
purposes
water
softening.
salts
any
Hard
with
water
soap

a
scum
14.1).
kettles
calcium
or
of
Hard
and
insoluble
water
water
also
pipes.
magnesium
calcium
forms
Soft
ions
can
remove
adding
calcium
sodium
(or
2+
and
and
carbonate
magnesium
(washing
magnesium
Mg
ions
from
2+
Ca
does
ions
from
soda).
carbonate)
is
A
distillation.
lot
of
its
This
an
of
is
has
created
in
scum
hard
water
precipitate
formed,
so
of
by:
calcium
removing
the
+
CO
(aq)
→
CaCO
removes
all
impurities,
but
it
is
expensive
because
a
used.
ion-exchange
run
(s)
3
When
through
ions
resin.
water
an
The
resin
containing
ion-exchange
replace
the
has
sodium
calcium
column,
sodium
ions
on
or
the
the
ions
bound
magnesium
calcium
surface
(or
of
the
(Figure
17.2.2).
When
each
calcium
ion
binds
to
the
resin,
these
two
features
hardly
a
hard
resin
water
is
surface.
magnesium)
evaporation
form
2−
(aq)
energy
using
ions
The
contains
not
solution.
3
to
water
and
(calcium
2+
Ca

magnesium
softening
carbonate

or
limescale
soap.
Water
You
forms
(see
inside
dissolved
with
17.2.1
moving
thin
water
Calcium
solution
carbonate)
Figure
by
a
through
washed
pollutants
part
for
hard.
describe
into
used
in

get
usually
water
treatment
domestic
water
well
and
carbonate.
in
are
temporary
rocks

as
minerals
leaching
water
and
of
soils,
leaching.
When
hardness
can
particles
differences
soft
permanent
Soil
nutrients
consequences
solvent
in
soil.
to:
In

substances
you
Harrison’s
sodium
ions
are
released
into
the
water.
The
sodium
ions
do
Cave,
not
make
the
water
hard.
Barbados.
T
emporary
T
emporary
magnesium
and
permanent
hardness
is
caused
by
hydrogencarbonates.
hardness
dissolved
It
can
be
calcium
removed
and
by
boiling,
2+
because
ions
the
hydrogencarbonates
precipitate
out
Ca(HCO
)
3
160
of
(aq)
2
decompose
and
the
Ca
solution.
→
CaCO
(s)
3
+
CO
(g)
2
+
H
O(l)
2
2+
and
Mg
Precipitation
of
calcium
carbonate
from
temporary
hard
water
builds
Water
up
as
a
‘fur’
inside
kettles
and
hot
water
in
pipes.
2+
2+
Ca
Permanent
hardness
cannot
be
removed
by
boiling.
It
is
caused
Ca
by
2
+
Ca
calcium
sulfate
and
magnesium
sulfate.
These
soluble
salts
do
not
+
Na
2
+
decompose
when
heated.
So
the
hardness
has
to
be
removed
Ca
using
+
Na
sodium
carbonate,
by
distillation
or
by
using
an
ion-exchange
resin.
Resin
+
Na
+
Na
Water
+
treatment
Na
+
Na
+
Water
can
be
purified
at
home
+
Na
by:
Na
+
+
Na

Boiling

Using
for
a
15
fine
minutes
fi lter
to
to
trap
kill
most
larger
microorganisms.
particles
and
larger
Water
and
smaller
microorganisms
are
not,
out
microorganisms.
Figure
Bacteria
Na
however,
17.2.2
Ion
removed.
exchange
because
stay

Chlorination.
A
chlorine-containing
bleach
or
water
on
the
the
are
chlorine
kills
Large-scale
1
Impure
added
all
the
water,
stirred,
then
left
for
30
minutes.
The
from
screens
water
particles,
added
is
is
to
to
of
water
rivers,
lakes
remove
stored
in
allowed
help
involves
and
large
several
The
water
underground
objects,
e.g.
wells
twigs,
passes
animal
DID
the
reservoirs
to
settle.
smaller
and
suspended
Aluminium
particles
sulfate
suspended
matter
,
or
in
e.g.
iron(III)
the
soil
of
sulfate
water
YOU
passes
through
a
sand
and
gravel
filter
.
This
suspended
particles
that
were
not
removed
in
the
to
is
settle.
‘furring
hot
the
removes
Carbon
may
be
added
to
remove
foul
smells
from
water
carbonate
water
from
as
Chlorine
is
added
to
kill
harmful
the
The
due
of
to
calcium
temporary
the
rate
of
hard
flow
in
the
pipes.
A
of
small
of
precipitate
can
be
an
water.
joints
however
,
in
the
because
pipework
it
and
microorganisms
the
risk
of
poisonous
bacteria.
copper
6
inside
reservoirs.
reduces
such
the
any
seals
Chlorination:
of
pipes
reduces
advantage,
5
up’
precipitation
amount
4
KNOW?
remains.
the
tiny
ions.
steps:
water
3
after
sodium
The
The
2
the
microorganisms.
purification
water
through
to
column
water
ions
purification
replacing
tablets
softens
calcium
pH
of
the
water
is
adjusted
and
then
run
off
for
homes
compounds
from
the
and
pipes
getting
into
drinking
water
.
factories.
KEY
1
POINTS
Leaching
they
2
removes
drain
Water
into
soluble
lakes
containing
and
compounds
from
the
soil
so
that
EXAM
rivers.
dissolved
carbon
dioxide
reacts
with
Y
ou
carbonate
rocks
to
form
hard
Hard
Soft
4
water
water
Hard
contains
does
water
distillation
can
or
aqueous
not
be
by
contain
made
using
calcium
these
soft
an
by
and
magnesium
ions.
ions.
using
washing
ion-exchange
soda,
Permanent
hardness
is
caused
by
no t
water
in
some
shou
ld
calcium
Temporary
the
sulfates.
hardness
is
know
caused
by
dissolved
the
purifi
catio
n
that
you
see
Y
ou
conc
entra
te
reaso
ns
fo r
and
and
6
to
abou
t
textb
ooks
.
se ttlem
ent,
magnesium
have
de tails
of
by
column.
dissolved
the
large-s
cale
on
5
do
water.
all
3
TIP
filtrat
ion
chlor
ination
.
calcium
hydrogencarbonate.
7
Temporary
hardness
hardness
cannot
be
can
be
removed
removed
by
by
boiling.
Permanent
boiling.
161
18
Green
chemistry
18.1
The
principles
green
What
LEARNING
is
the
end
of
this
topic
be
green
able
of
more
the
of
a
air,
define
green
outline
the
and
with
land
around
increasing
us
is
world
becoming
population
more
and
to:
problems.
chemistry
the

water
problem
industrialisation.

chemistry?
you
and
should
chemistry
OUTCOMES
Pollution
At
of
principles
of
In
Green
environment
15.6
and
16.4
chemistry
in
the
first
we
deals
place.
explored
with
It
how
does
some
to
this
of
these
prevent
by
harming
improving
chemical
green
processes
and
manufacturing
techniques
for
making
materials
such
chemistry
as

understand
the
plastics,
the
and
glass.
It
also
improves
the
way
that
metals
application
are
of
clothing
principles
of
extracted
from
their
ores
and
the
way
that
bulk
chemicals,
such
as
green
sulfuric
acid,
are
made.
Most
products
are
made
through
a
series
of
chemistry.
chemical
may
The
reactions
require
main
one
(chemical
or
more
problems
synthesis).
reactants
arising
from
as
the
YOU
Some
score
have
chemical
out
as
Catalyst
reaction
a
catalyst
in
this
series
(Figure
industry
18.1.1).
are:
manufacture
KNOW?
scientists
giving
well
chemical
Petroleum
DID
Each
of
suggested
processes
100
for
Naphtha
Catalyst
a
‘greenness’
Hydrogen
based
on
atom
Removal
economy,
Nitrogen
of
Ammonia
Reaction
(air)
CO
+
CO
(low
vessel
yield)
2
price
of
reactants,
requirements
impact.
The
by
environmental
conversion
nitrobenzene
aniline
and
energy
to
a
modern
dye
of
Unreacted
called
has
a
‘greenness’
18.1.1
Ammonia
manufacture
more
than
just
the
reaction
of
hydrogen
nitrogen.
64/100.

the
use
and

inefficient

low
production
energy
percentage
use,
of
e.g.
yield
hazardous
high
and
low
amount
percentage
yield
of
economy
order
the
idea
Green
to
reduce
of
green
chemistry
eliminates
the
manufacture
is
and
pressures
economy.
required
product
obtained
amount
mass
of
of
product
required
some
of
defined
and
use
masses
these
(also
as:
a
all
the
problems,
called
set
generation
of
of
chemical
of
of
product
100
products
scientists
sustainable
principles
hazardous
products.
100
expected
×
chemistry
use
atom
and
=
molar
In
temperatures
×
molar
atom
substances
=
maximum
162
is
score
and
of
recycled
chemical
Figure
methods
gases
that
have
developed
chemistry).
reduces
substances
in
or
the
The
twelve
principles
of
green
chemistry
DID
The
twelve
principles
of
green
chemistry
Prevention:
has
been
It
is
better
to
reduce
waste
than
to
treat
it
after
Enzymes
to
it
the
Atom
economy:
The
methods
used
for
synthesis
should
use
many
of
the
materials
used
in
the
process
as
possible
very
They
these
into
the
required
product.
In
other
atom
economy
should
be
as
near
100%
as
not
generally
Less
hazardous
products
and
chemical
catalysts
synthesis:
to
the
The
harm
environment
of
and
and
reactants,
life
should
be

9
products:
The
effectiveness
of
the
be
reduced
at
the
same
time
as
be
decreasing
used
Safer
so
and
harmful
separation
6
techniques
energy
should
used.
be
other
agents:
solvents,
Minimum
the
Reactions
catalysts
are
not
used
requirements:
The
reactions
and
As
or
their
little
should
should
be
substances
use
is
energy
be
as
The
for
hot
Use
heat
another
evolved
job
be
and
raw
renewable
in
exothermic
not
released
reactions
to
the
materials:
Raw
at
r.t.p.
should
has
is
a
instead
material
undergone
material
naphtha
e.g.
1
Green
of
of
taken
depleting
from
and
natural
nature
(or
a
some
slight
processing)
for
fraction
a
chemical
from
process,
petroleum
air,
use
of
additional
or
substance
is
synthesised
in
several
is
used
iron
as
chemistry
or
is
a
that
and
eliminates
generation
the
of
substances
manufacture
ore,
steps:
particular
and
in
use
of
the
products.
the
2
additional
steps,
among
resources.
The
manufacture
of
involves
a
chemical
series
When
of
a
12
feedstocks
distillation.
chemicals
and
substance
that
e.g.
5
principles
products
Reduce
or
fits
POINTS
chemical
8
CFCs
This
if
the
starting
of
be
environment,
materials
3,
hazardous
feedstock
that
of
instead
possible
out
use
A
dioxide)
solvent
others.
set
renewable
should
a
hydrocarbons.
principles
in
water.
of
as
manufacture
reduces
7
dioxide
carbon
minimised.
as
carried
devised
used
KEY
possible.
used
6
harm.
solvents
that
3,
their
toxic
5
inorganic
others.
carbon
polystyrene
possible
using
products
in
not
than
principles
(supercritical
chemical
should
rather
fits
among
Liquid
can
Safer
harmful.
product
possible.
minimised.
4
a
words,
catalysts
3
at
and
and
enzymes
the
work
temperature
Synthesising
incorporate
specific
they
up
are
as
are
reactions
catalyse.
formed.
room
2
KNOW?
are:

1
YOU
chemical
reactions
(a
chemicals
synthesis).
(blocking
groups)
unwanted
ways.
are
The
used
to
blocking
stop
reactive
groups
are
groups
reacting
removed
in
later.
3
Green
to
9
Use
of
catalysts:
The
use
of
catalysts
reduces
energy
chemistry
reduce
the
the
reaction
takes
place
at
a
lower
temperature.
specific
the
catalyst
for
a
particular
reaction
is,
the
less
likelihood
of
getting
additional
unwanted
reduce
Nature
of
breakdown
of
products:
Products
should
be
that
they
break
down
in
the
environment
to
form
The
breakdown
products
should
and
for
a
long
not
stay
in
Monitoring
to
prevent
pollution:
Each
step
in
a
should
methods
be
monitored
should
where
take
use
pollutants
or
Monitoring
for
the
presence
of
reaction
be
developed
to
control
the
Minimise
chemical
the
and
their
release
into
the
accidents:
The
products
should
be
taken
of
pollutants
reaching
the
are
preferable
environment.
hazards
into
course
prevention
of
presented
by
treating
account.
Conditions
pollutants
after
reactants
they
and
r.t.p.
pollutants
formation
to
12
at
catalysts.
environment
these
possible,
place
chemical
of
and
the
processes.
time.
a
synthesis
the
the
5
11
increase
of
Reactions,
and
environment
of
harmless
should
substances.
waste
designed
4
so
the
products.
efficiency
10
in
is
energy
the
used
The
reaction,
more
of
costs
chemicals
because
seeks
waste
have
entered
the
chosen
environment.
should
minimise
these.
163
18.2
Examples
of
green
chemistry
Example
LEARNING
Maleic
At
the
end
1:
Maleic
anhydride
OUTCOMES
of
this
topic
anhydride
is
used
in
the
manufacture
of
polyester
resins
paints.
It
was
formerly
manufactured
by
heating
benzene,
C
H
6
should
be
able
understand
the
in
the
presence
application
H
6
the
with
6
principles
of
of
a
catalyst:
1
C
of
,
to:
oxygen

and
you
+
4
O
2
6
→
C
2
H
4
O
2
+
2CO
3
+
2H
2
O
2
green
benzene
maleic
anhydride
chemistry
It

explain
why
process
or
a
given
is
now
manufactured
procedure
is
an
H
4
of
green
+
3
O
2
10
→
C
2
H
4
O
2
+
4H
3
O
2
chemistry.
butane
The

EXAM
butane:
1
C
example
from
chemical
process
The
atom
maleic
using
butane
economy
in
is
anhydride
‘greener’
terms
of
because:
carbon
is
better.
There
is
no
loss
of
TIP
carbon.

Y
ou
do
no t
need
to
No
carbon
global
an
in -d
epth
green
de tails
of
exam
ples.
need
to
stud
y
chem
istry
to
or
do,
the
Example
Coal
green
and
have
how
to
that
provi
ded,
so lven
ts
the
reaction
does
not
increase
Treating
oil-fired
power
steps
to
emissions
stations
control
the
and
other
release
of
industries
harmful
burning
gases
into
fossil
the
fuels
air
.
Flue
gas
desulfurisation
is
used
to
remove
sulfur
dioxide
arising
chem
istry
exam
ples
been
2:
take
from
to
So
princip
les

of
produced.
give
howe
ver
,
unde
rstand
apply
is
warming.
of
parti
cular
Y
ou
dioxide
mak
e
are
have
e.g.
burning
sulfur
some
is
harm
ful,
fossil
dioxide
kept
in
harmless
are
constant
calcium
fuels
containing
passed
through
movement.
sulfite,
The
CaSO
sulfur.
The
powdered
sulfur
gases
calcium
dioxide
containing
oxide,
reacts
to
which
form
:
3
so
search
for
alterna
tive
SO
(g)
+
CaO(s)
→
CaSO
2
harm
less
The

calcium
Filters
and
sulfite
are
used
power
collects
To
on
can
to
used
remove
stations.
the
be
Air
outside
is
to
dust
make
and
drawn
(see
Catalytic
gases
over
Air
a
particles
through
Figure
as
The
carbon
exhaust
platinum
are
converted
converted
Polyester
from
chemical
filters
and
plants
dust
18.2.1).
or
are
used
monoxide
gases
to
from
rhodium
reduce
and
Dirty
Bag
dust
filters
from
are
used
waste
the
nitrogen
the
catalyst.
to
to
harmless
harmless
2NO(g)
+
nitrogen.
car
emission
oxides
engine
Harmful
carbon
2CO(g)
Toxic
are
of
from
harmful
petrol
passed
nitrogen
air
to
in
collect
gases.
carbon
oxides
monoxide
dioxide.
→
N
(g)
2
'sock'
collecting
164
the
acid.
sucked
through
Dust
converters
such
engines.
18.2.1
sulfuric
chimney

Figure
(s)
3
ones.
+
2CO
(g)
2
is
Example
A
chemical
carpets
a
3:
called
and
product
Making
bacteria.
arising
The
can
be
The
process

The

Less
from
can
on
cracking
now
be
does
not
is
to
make
from
polyesters
propene.
naphtha
fraction
by
genetically
using
bacterium
of
for
Propene
is
petroleum.
modified
Escherichia
coli
(E.
coli)
corn.
‘greener’
depend
is
used
made
made
because:
directly
Renewable
dioxide
is
is
the
modified
bacteria
petroleum.
carbon
chemical
mashed-up
using
process
as
The
genetically
grown
such
propene-1,3-diol
clothing.
Propene-1,3-diol
polyesters
corn
produced.
on
is
So
non-renewable
used
there
as
is
a
resources
feedstock.
less
effect
on
Figure
the
18.2.2
Escherichia
bacteria).
coli
(E.coli
Genetically
environment.
modified

The
are
energy
costs
are
lower
because
on
average
lower
temperatures
to
used.
make
‘green’

The
process
Example
Chemists
plants)
6–12
4:
are
to
uses
atoms
of
algae.
in
water
mixture.
suitable
‘greener’
Methane
strains
with
or
and
the
small
ways
be
using
produced
produce
in
amounts
is
the
of
algae
The
algae
the
are
the
The
absorb
carbon
reduce
global
produced
well.
in
does
not
depend
directly
on
non-renewable
bonus
Algae
as
dioxide
‘carbon

The
energy

The
process
is
absorbed
for
photosynthesis,
so
the
process
from
Example
costs
are
uses
5:
attach
an
lower
because
efficient
the
catalyst:
process
enzymes
Using
an
improved
occurs
in
the
at
KEY
r.t.p.
the
C
H
6
an
alkyl
presence
+
CH
6
group
of
an
to
benzene,
aluminium
CH = CH
3
added
(quenching).
be
C
H
(nitrates
the
and
waste
to
The
works.
,
by
→
C
2
H
6
the
reaction
to
stop
CH(CH
5
reacting
it
with
water
reacts
with
the
to
bacteria
produce
useful
for
synthesis.
an
catalyst.
2
Algae
can
be
used
to
fuels.
)
3
more
modified
used
6
chloride
2
alkyl
groups
being
Flue
catalyst,
forming
gas
desulfurisation,
filters
added
catalytic
converters
are
hydrogen
used
to
reduce
the
emission
gas.
of
When
from
Genetically
and
chloride
as
grown
environments
compounds
3
is
algae
be
POINTS
produce
Water
The
could
algae.
catalyst
6
in
the
also
sewage
chemical
can
from
fuels
neutral’.
can
alkene
and
is
1
We
dioxide
that
in
oceans
petroleum.
Carbon
almost
grown
resources
water

a
suggested
the
nutrients
phosphates)
such
in
warming.
could
controlled
the
is
be
in
so
be
is
because:
process
propene
this
used
way.
have
should
to
added
are
process
scientists
quantities
using

of
be
KNOW?
algae
huge
of
through
YOU
Some
that
particular
hydrocarbons
fractionation,
(simple
containing
presence
bubbled
can
bacteria.
from
butanol.
dioxide
petroleum
of
hydrocarbons
reservoirs
Carbon
relatively
compared
in
DID
new
can
can
vessels
nutrients.
enzymes
algae
molecule
glass
Although
produced
per
Other
in
catalyst:
investigating
biofuels.
grown
and
from
currently
strains
light
efficient
Fuels
make
carbon
an
strains
bacterium
the
catalyst
is
‘greener’

The

No
is
modified
by
combining
it
with
silica,
the
process
the
compounds
into
atmosphere.
because:
4
yield
harmful
is
higher.
corrosive
fumes
Improvements
can
of
hydrogen
chloride
are
produced.
and
lead
a
to
in
catalysts
greater
reduction
in
yields,
harmful
emissions.

The
catalyst
can
be
filtered
and
reused.
165
19
Qualitative
19.1
analysis
Identification
T
ests
LEARNING
the
end
of
this
topic
be
able
to
identify
the
2+
Ca
by
ions
2+
,
Zn
Pb
2+
,
colour
hydroxide
metal
cations
precipitate
can
formed
be
by
identified
the
by
addition
observing
of
dilute
the
colour
sodium
of
hydroxide
Fe
and
Al
,
3+
,
Fe
in
aqueous
hydroxide
is
solution
not
in
of
excess,
the
a
substance
metal
under
hydroxide
test.
is
If
the
formed.
sodium
In
excess
2+
,
sodium
Cu
solubility
hydroxides
an
3+
,
hydroxide,
some
of
the
precipitates
may
dissolve.
of

the
sodium
to:
2+

using
you
the
should
cations
cations
OUTCOMES
Many
At
for
of
If
a
white
precipitate
forms,
which
is
insoluble
in
excess
sodium
aqueous
2+
hydroxide,
sodium
hydroxide
identify
the
a
Group
II
cation
such
as
Ca
,
may
be
present.
2+
Ca
2+

2+
Ca
ions
2+
,
Zn
Pb
2+
,
Fe
Al
3+
,
Fe
(aq)
+
2OH
(aq)
→
Ca(OH)
3+
,
(s)
2
,
2+
,

Cu
If
a
white
precipitate
is
formed
that
dissolves
when
excess
3+
by
colour
and
solubility
hydroxide
of
is
added
to
give
a
colourless
solution,
Al
,
sodium
2+
Pb
or
2+
the
hydroxides
in
Zn
aqueous
ions
may
aluminates,
ammonia
be
present.
plumbates
or
This
is
due
to
the
formation
of
soluble
zincates.
2+

identify
Pb
potassium
ions
sodium
using
hydroxide
not
in
excess:
3+
iodide
Al
(aq)
+
3OH
(aq)
→
Al(OH)
(s)
3
+

identify
NH
ions
by
evolution
in
4
of
ammonia
on
warming
excess
sodium
hydroxide:
with
Al(OH)
(s)
+
OH
(aq)
→
Al(OH)
3
aqueous
sodium
aluminium

write
ionic
equations
for
hydroxide
aluminate
ion
the
The
reactions
(aq)
4
hydroxide
equations
for
lead( II)
hydroxide
and
zinc
hydroxide
dissolving
in
above.
excess
sodium
hydroxide
are:
2−
Pb(OH)
(s)
+
2OH
(aq)
→
Pb(OH)
2
DID
YOU
KNOW?
lead( II)
(aq)
4
hydroxide
plumbate(
II)
ion
2−
Zn(OH)
Some
transition
element
cations
give
their
a
characteristic
aqueous
copper(II)
solution
ions
are
containing
colour
solutions,
in
iron(II)
blue,
ions

If
a
coloured
identify
solutions
are
+
2OH
(aq)
→
Zn(OH)
(aq)
4
hydroxide
zincate
ion
to
e.g.
aqueous
often
(s)
2
zinc
is
the
insoluble
precipitate
cation
in
often
is
(Figure
excess
formed,
19.1.1).
sodium
the
A
colour
metal
may
be
hydroxide
used
is
to
formed
that
hydroxide.
2+
Fe
(aq)
+
2OH
(aq)
→
Fe(OH)
(s)
2
light
green,
solutions
containing
iron( II)
iron(III)
ions
are
often
ions
iron(
II)
hydroxide
yellow.
grey-green
gelatinous
precipitate
3+
Fe
(aq)
+
3OH
(aq)
→
Fe(OH)
(s)
3
iron( III)
ions
iron(
red-brown
III)
hydroxide
gelatinous
precipitate
2+
Cu
(aq)
+
2OH
(aq)
→
Cu(OH)
(s)
2
copper( II)
ions
copper(
pale
T
ests
for
Aqueous
cations
ammonia
observations
Figure
19.1.1
Transition
can
be
from
their
166
metal
ions
identified
the
colour
of
hydroxides.
same
There
as
the
are
and
contains
ionic
reactions
some
using
equations
and
ionic
exceptions:
blue
aqueous
hydroxide
for
II)
most
precipitate
ammonia
ions
equations
hydroxide
(see
of
7.2).
the
using
The
reactions
sodium
are
the
hydroxide.
2+

3+
Zn
ions
the
use
can
of
be
distinguished
aqueous
ammonia.
from
Zinc
2+
Al
ions
and
hydroxide
Pb
ions
dissolves
in
by
excess
EXAM
aqueous
ammonia
hydroxide
and
to
lead
form
a
colourless
hydroxide
do
not
solution.
dissolve.
When
NH
(aq)
not
in
TIP
Aluminium
excess:
test
3
cond
uctin
g
fo r
Fe(II)
ions,
the
do
no t
2+
Zn
(aq)
+
2OH
(aq)
→
Zn(OH)
(s)
leave
2
NH
(aq)
in
eithe
r
the
contai
ning
excess:
iron(
II)
3
ions
2+
Zn(OH)
(s)
+
4NH
2
(aq)
→
Zn[(NH
3
)
3
Copper
deep
NH
hydroxide
blue
(aq)
dissolves
in
excess
(aq)
+
2OH
(aq)
(after
solution
in
the
precip
itate
aqueous
ammonia
to
form
addi
ng
hydr
oxide)
a
fo r
too
are
readi
ly
solution.
not
or
4
colourless

]
so lutio
n
sodium
in
long.
the
air
Iron(
II)
oxidis
ed
excess:
ions
by
3
oxyg
en
in
the
2+
Cu
(aq)
+
2OH
(aq)
→
Cu(OH)
(aq)
in
to
(s)
2
NH
air
Fe(III)
ions.
T
hat
is
why
excess:
a
3
precip
itate
of
iron(
II)
2+
Cu(OH)
(s)
+
4NH
2
(aq)
→
Cu[(NH
3
deep
A
confirmatory
Aqueous
give
solutions
white
of
is
to
lead(II)
are
add
with
soluble
some
iodide
is
for
containing
precipitates
precipitates
ions
test
in
)
3
lead(II)
lead
and
sodium
excess
aqueous
blue
(aq)
potassium
2OH
(aq)
hydr
oxide
solution
aluminium
A
+
quite
turn
s
brow
n
quick
ly.
ions
hydroxide
alkali.
]
4
or
ions
confirmatory
iodide.
both
ammonia.
A
test
yellow
Both
for
lead( II)
precipitate
formed:
Red
litmus
paper
2+(
Pb
aq)
+
2I
(aq)
→
PbI
(s)
2
Aluminium
potassium
ions
do
not
give
a
precipitate
on
addition
of
aqueous
iodide.
Ammonium
+
T
esting
for
ammonium
sodium
compound
hydroxide
ions
Warm
gently
+
When
a
compound
containing
ammonium
ions,
NH
,
is
heated
4
gently
with
Ammonia
aqueous
turns
red
sodium
litmus
hydroxide,
blue
(see
ammonia
Figure
is
given
Figure
off.
19.1.2
Red
litmus
when
19.1.2).
a
turns
solution
blue
containing
+
NH
ions
is
warmed
with
4
+
NH
(aq)
+
OH
(aq)
→
NH
4
KEY
+
H
3
O(l)
aqueous
sodium
hydroxide.
2
POINTS
2+
1
(g)
Solutions
containing
Ca
2+
,
Pb
2+
,
Zn
4
or
Precipitates
of
zinc
hydroxide
or
copper
3+
Al
of
ions
give
sodium
when
the
white
precipitates
hydroxide
sodium
or
on
aqueous
hydroxide
or
hydroxide
addition
in
ammonia
2+
Solutions
give
containing
coloured
aqueous
is
Cu
2+
,
precipitates
Fe
In
aqueous
solution,
on
hydroxide
or
addition
aqueous
lead( II)
hydroxides
of
aluminium,
dissolve
in
ions
to
react
from
a
with
yellow
ions
precipitate.
Ammonia
is
released
when
an
aqueous
ammonia.
lead
excess
iodide
of
solution
Precipitates
potassium
3+
or Fe
6
sodium
3
excess
excess.
aqueous
2
in
ammonia.
ammonia
5
not
dissolve
or
zinc
aqueous
of
ammonium
sodium
ions
is
heated
with
hydroxide.
sodium
hydroxide.
167
19.2
Identification
Identifying
LEARNING
the
end
carbonates
of
this
topic
All
carbonates
reacts
with
CO
be
able
acids
to
produce
carbon
dioxide,
e.g.
you
2−
should
anions
OUTCOMES

At
of
to:
+
(s)
+
2H
(aq)
→
CO
3
The
(g)
+
H
2
carbon
dioxide
released
turns
O(l)
2
limewater
milky
(Figure
19.2.1).
2−

identify
the
anions
CO
3

and
NO
when
Many
carbonates
decompose
to
form
carbon
dioxide
when
strongly
compounds
3
heated,
containing
heated
these
ions
e.g.
are
SrCO
strongly
(s)
→
SrO(s)
+
CO
3
(g)
2
2−

identify
the
anions
CO

and
Soluble
carbonates
form
a
white
precipitate
on
addition
of
barium
3
2−
SO
by
the
gases
nitrate
produced
or
barium
chloride.
3
when
reacted
with
dilute
2−
acids
CO
2+
(aq)
+
Ba
(aq)
→
BaCO
3

describe
the
ions
using
lead
nitrate
test
silver
for
halide
nitrate
The
precipitate
describe
ions
the
using
test
for
barium
write
ionic

chloride
The
equations
for
dilute
acid,
releasing
carbon
dioxide.
sulfates
solution
to
be
tested
Aqueous
is
first
barium
acidified
chloride
or
with
nitric
barium
acid
nitrate
to
is
remove
then
any
added.
the
If
reactions
in
sulfate
carbonates.

dissolves
or
Identifying

(s)
3
a
sulfate
is
present,
a
white
precipitate
of
barium
sulfate
is
observed.
above.
2+
Ba
2−
(aq)
+
SO
(aq)
→
BaSO
4
The
precipitate
does
(s)
4
not
dissolve
on
addition
of
dilute
acid.
Limewater
Identifying
sulfites
2−

Sulfites
contain
the
ion
SO
Acid
.
When
an
aqueous
sulfite
is
heated
3
with
a
dilute
acid,
sulfur
dioxide,
SO
,
is
released.
2
Carbonate
2−
SO
+
(aq)
+
2H
(aq)
→
SO
3
Figure
19.2.1
A
carbonate
on
the
addition
gas
is
present
of
an
released
limewater
YOU
Sulfur
dioxide
paper
red.
milky.
through
more
is
to
reliable
test
for
a
aqueous
a
Its
has
a
choking
presence
solution
of
and
is
to
the
warming,
released
if
Aqueous
turns
damp
turns
bubbling
blue
manganate( VII).
from
purple
to
The
the
litmus
gas
solution
colourless
if
of
sulfur
sulfites
form
a
suspected
white
precipitate
with
barium
nitrate
or
ammonia
nitrate
is
2+
(aq)
+
Ba
The
is
precipitate
dissolves
of
AgI
AgCl
(left),
(right)
(s)
in
dilute
acid,
releasing
sulfur
dioxide
Many
nitrates
nitrates
decompose
nitrogen
–
Nitrogen
–
Oxygen
when
the
solid
nitrate
is
heated
to
dioxide.
)
3
and
BaSO
3
2Cu(NO
AgBr
→
heating.
present.
Precipitates
(aq)
3
nitrate.
release
19.2.2
a
aluminium

168
It
by
chloride.
Identifying
Figure
smell.
confirmed
potassium
manganate( VII)
2−
On
acidic
be
present.
SO
powder
can
sodium
barium
hydroxide
O(l)
2
nitrate

add
H
KNOW?
dioxide
A
+
acid,
turns
potassium
DID
(g)
2
if
dioxide
relights
→
2CuO(s)
+
4NO
2
can
a
(g)
+
2
be
identified
glowing
splint
as
(see
a
brown,
19.3).
O
(g)
2
choking
gas.
on
Not
all
test
for
nitrates
decompose
oxygen
is
the
most
to
form
reliable
nitrogen
dioxide
indication
of
the
(see
15.2).
presence
of
So
a
the
nitrate.
EXAM
Identifying
T
he
halides
TIP
effect
of
carbon
ates,
Using
aqueous
silver
Add
dilute
nitric
acid
to
an
aqueous
solution
of
the
suspected
Then
sulfa
tes
satis
facto
ry
halide.
2
aqueous
silver
precipitate
(Figure
Add
aqueous
nitrate
and
observe
the
colour
of
the
than
other
becaus
e
19.2.2).
excess
ammonia
and
see
if
the
precipitate

Chlorides
give
a
white
+
Ag
precipitate
of
silver
chloride:
silver
and
decom
pose
less
of
catio
ns
T
his
is
carbon
ates,
sulfa
tes
decom
pose
at
or
do
only
tempe
ratures
−
(aq)
+
Cl
(aq)
→
higher
AgCl(s)
than
Buns
en
The
tests.
dissolves.
not
a
these
some
nitra
tes
3
is
meth
od
identif
ying
add
on
nitrate
and
1
heat
nitra
tes
chloride
precipitate
dissolves
readily
in
a
little
aqueous
that
burn
er
of
a
flam
e.
ammonia.

Bromides
give
a
cream-coloured
+
Ag
The
silver
aqueous

Iodides
precipitate
of
silver
bromide:
−
(aq)
+
bromide
Br
(aq)
→
precipitate
AgBr(s)
dissolves
only
in
excess
concentrated
ammonia.
give
a
pale
yellow
precipitate
of
silver
iodide:
KEY
+
Ag
(aq)
+
I
(aq)
→
AgI(s)
1
The
silver
POINTS
−
iodide
precipitate
does
not
dissolve
in
Carbonates
dioxide
concentrated
aqueous
Some
aqueous
lead
when
Add
dilute
nitric
heated
produce
and
nitrates
oxygen.
produce
nitrate
nitrogen
1
carbon
ammonia.
nitrates
Using
produce
excess
acid
to
an
aqueous
solution
of
the
dioxide
when
suspected
heated.
halide.
2
2
Then
add
aqueous
lead
nitrate
and
observe
the
colour
of
When
reacted
with
dilute
the
acids,
carbonates
produce
precipitate.
carbon

Chlorides
give
a
white
2+
Pb
precipitate
of
lead( II)
dioxide
produce
chloride:
sulfur
and
sulfites
dioxide.
−
(aq)
+
2Cl
(aq)
→
PbCl
(s)
3
Aqueous
solutions
of
halide
2

Bromides
give
a
pale
yellow
2+
Pb
precipitate
of
lead
ions
bromide:
or
−
(aq)
+
2Br
(aq)
→
PbBr
react
lead
with
nitrate
silver
to
nitrate
form
(s)
2
characteristically

Iodides
give
a
deep
yellow
precipitate
of
lead
coloured
iodide:
precipitates.
2+
Pb
−
(aq)
+
2I
(aq)
→
PbI
(s)
2
4
Barium
nitrate
chloride
Warming
with
concentrated
sulfuric
gives
Chlorides

Bromides

Iodides
produce
produce
produce
a
white,
acidic
fumes
orange-brown
black
solid
of
fumes
(iodine)
a
barium
white
acid
precipitate

or
hydrogen
of
and
chloride.
bromine
a
purple
solutions
or
vapour.
iodine
vapour.
5
with
of
aqueous
sulfates,
sulfites
carbonates.
When
warmed
concentrated
acid,
halides
with
sulfuric
produce
characteristically
coloured
products.
169
19.3
Identification
Identifying
LEARNING
At
the
end
should
be
identify
of
this
able
topic
,
gases
SO
3
,
Cl
2
with

Hydrogen

When
H
,
,
O
,
CO
2
NO
2
H
,
O
2
to

a
to
CO
and
or
,
H
2
write
has
no
smell.
a
lighted
with
splint
a
is
put
squeaky
into
a
test
tube
of
hydrogen,
it
‘pop’.
O
2
Identifying
oxygen
and
reference

Oxygen

When
is
a
colourless
glowing
gas.
splint
It
is
has
put
no
into
smell.
glowing
NH
,
SO
3
O
by
,
splint
in
a
test
tube
of
oxygen,
the
splint
Cl
2
relights.
,
2
Identifying
specific
carbon
dioxide
reactions
equations
reactions
for
where

Carbon

When
dioxide
is
a
colourless
carbon
dioxide
is
hydroxide),
due
to
Ca(OH)

On
the
(aq)
to
CaCO
is
tests
(splin
t)
and
hydr
ogen
splin
t
has
a
+
CO
and
(g)
of
a
→
goes
limewater
+
of
soluble
CO
(g)
milky
(a
suspension
CaCO
(s)
+
(Figure
of
H
3
bubbling
form
(s)
carbon
calcium
+
H
2
A
second
way
of
dioxide
solution
of
O(l)
19.3.1(a)).
calcium
carbonate:
O(l)
2
dioxide,
the
calcium
carbonate
hydrogencarbonate:
→
Ca(HCO
2
)
3
(aq)
2
testing
is
shown
for
in
the
presence
Figure
of
small
amounts
of
19.3.1(b).
ligh ted
Gas
a
the
the
through
oxyg
en.
that
has
smell.
fo r
carbon
Rem
embe
r
no
to

hydr
ogen
bubbled
limewater
formation
3
error
the
has
2
continued
dissolves
TIP
confus
e
is
the
2
comm
on
It
relevant.
This
EXAM
gas.
the
calcium
A
It
2
chemical

gas.
,
H
colour
with
2
NO
colourless
2
lighted
identify
a
2
and
2
reference
identify
is
you
smell

hydrogen
to:
2
NH
gases
OUTCOMES
explodes

of
H
a
O
b
fo r
Glass
rod
glow
ing
fo r
Limewater
oxyg
en.
Limewater
Gas
DID
In
YOU
the
KNOW?
presence
of
water
,
sulfur
Figure
dioxide
agent
and
is
used
for
as
fibres
wool.
It
a
such
reacts
19.3.1
T
wo
as
form
which
The
hydrogensulfite
are
a
reducing
bleaching
Chlorine
on
action
the
bleach
for
carbon
dioxide
agent.
is
other
and
ammonia
ions,

Ammonia
is
a
colourless

Ammonia
turns
gas.
It
has
a
sharp
smell.
gentle.
hand
is
works
damp
red
litmus
paper
blue.
Hydroxide
when
ammonia
reacts
with
the
water
in
the
damp
by
The
hydroxide
ions
turn
the
litmus
indicator
stains.
+
NH
(g)
3
170
ions
are
a
paper.
oxidising
testing
water
formed
stronger
of
silk
with
Identifying
to
ways
bleaching
+
H
O(l)
2
NH
(aq)
4
−
+
OH
(aq)
blue.
litmus

White
fumes
of
ammonium
chloride
are
seen
when
a
drop
of
Drop
concentrated
hydrochloric
acid
on
the
end
of
a
glass
rod
is
of
Glass
placed
rod
concentrated
near
the
gas
(Figure
19.3.2).
hydrochloric
(g)
NH
+
HCl(g)
NH
3
acid
Cl(s)
4
White
fumes
Identifying
hydrogen
chloride
Ammonia

Hydrogen
chloride
is

Hydrogen
chloride
can
aqueous
ammonia
ammonium
near
the
on
chloride
hydrogen
a
colourless
be
the
are
gas.
identified
end
seen
of
a
It
has
using
glass
when
the
a
a
pungent,
drop
rod.
drop
of
smell.
concentrated
White
of
acidic
fumes
ammonia
of
is
Figure
19.3.2
White
placed
fumes
ammonium
are
chloride.
formed
hydrogen
which
Identifying
sulfur
acid,

Sulfur
dioxide

When
sulfur
is
a
colourless
dioxide
manganate(VII),
the
is
gas.
bubbled
potassium
when
It
has
a
through
pungent
aqueous
manganate( VII)
acidic
the
chloride,
evaporates
concentrated
dioxide
of
chloride
reacts
from
hydrochloric
with
ammonia.
smell.
potassium
turns
from
purple
to
colourless.

When
sulfur
dioxide
dichromate(VI),
the
is
bubbled
potassium
through
aqueous
dichromate( VI)
potassium
turns
from
orange
to
green.
Identifying
nitrogen
dioxide
KEY

Nitrogen
dioxide
is
a
poisonous
red-brown
gas.
It
has
a
sharp
1
irritating
Hydrogen
Nitrogen
dioxide
turns
damp
blue
litmus
paper
red.
The
lighted
identified
splint.
using
reacts
with
the
water
in
the
damp
litmus
paper
Oxygen
is
nitrogen
identified
dioxide
is
smell.
a

POINTS
to
form
using
a
glowing
an
splint.
acidic
solution.
2
Identifying
Chlorine
is
a
poisonous
yellow-green
gas.
It
has
a
sharp,
milky.
Ammonia
turns
Chlorine
turns
damp
blue
litmus
paper
red
and
then
paper
see
it.
blue.
Sulfur
dioxide
The
the
bleaching
litmus
paper
reaction
being
is
often
bleached.
so
fast
The
decolourises
rapidly
that
you
chlorine
manganate( VII)
may
and
only
turns
potassium
reacts
dichromate(VI)
with
the
water
in
the
damp
litmus
paper
and
forms
a
mixture
hydrochloric
and
bleaching
chloric( )
acids.
The
chloric( )
acid
is
(g)
+
H
2
responsible
for
O(l)
→
HCl(aq)
+
HClO(aq)

Water
vapour
water
is
vapour
colourless.
It
has
Water
vapour
turns
dry

Water
vapour
turns
anhydrous
blue.
chloride
fumes
with
forms
ammonia.
2

to
Hydrogen
white
6
Identifying
orange
green.
action.
5
Cl
from
of
to
the
red
smell.
potassium
bleaches
damp
choking
4

turns
limewater
litmus
bleach-like
dioxide
chlorine
3

Carbon
cobalt
Nitrogen
brown
no
smell.
chloride
paper
copper( II)
7
from
sulfate
blue
crystals
to
white
is
a
red-
Chlorine
bleaches
damp
litmus.
pink.
from
dioxide
gas.
8
Water
cobalt
and
vapour
turns
chloride
anhydrous
sulfate
blue
paper
pink
copper
blue.
171
Section
SECTION
1
Which
about
the
C:
of
C
Practice
Multiple-choice
the
statements
metallic
periodic
a
Metallic
b
Solid
and
is
exam
questions
questions
generally
non-metallic
true
elements
5
of
Which
of
of
green
the
following
statements
is/are
true
chemistry?
table?
elements
have
non-metallic
low
melting
elements
are
I
It
prevents
waste.
II
It
improves
III
It
uses
points.
energy
efficiency.
shiny
renewable
feedstocks.
looking.
c
Non-metallic
of
d
elements
are
poor
a
I
only
b
I
and
c
II
and
d
I,
II
conductors
II
electricity.
Metallic
elements
are
poor
conductors
III
of
and
III
heat.
6
2
Metal
salts
can
be
prepared
from
a
Which
of
the
preparation
insoluble
metal
carbonate
in
dilute
of
excess
solid
the
following
is
mixed
best
with
explains
the
of
methods
hydrogen
gas
of
should
not
be
acid.
attempted
Which
following
water
in
the
laboratory?
why
a
acid?
Reacting
sodium
with
dilute
hydrochloric
acid
a
To
produce
b
To
speed
c
It
d
All
is
up
easier
the
good
the
to
acid
crystals
filter
is
b
Reacting
magnesium
c
Electrolysis
d
Reacting
the
acid
neutralised
than
and
the
can
be
the
of
Which
element
other
because
it
is
used
situations
has
for
window
magnesium
Silver
b
Zinc
Which
good
exposed
to
the
anti-corrosion
statement
d
Copper
is
true
about
the
properties
water?
a
The
temperature
c
of
water
rises
and
falls
quickly.
Water
polar
Aluminium
dilute
weather,
properties?
b
c
with
acid
frames
very
a
water
filtered.
of
and
acidified
excess
7
3
steam
solid.
hydrochloric
solid
with
reaction
is
a
good
solvent
because
it
has
a
nature.
Water
molecules
do
not
cling
to
each
other.
4
Which
of
the
following
is
not
matched
d
Water
changes
to
steam
by
condensation.
correctly?
8
172
Which
of
Non-metal
Use
a
Hydrogen
Manufacture
b
Phosphorus
In
c
Chlorine
Ceramics
d
Silicon
Electronic
of
ammonia
matches
devices
the
of
the
use
of
following
coke
a
It
oxidises
b
It
acts
c
It
is
d
It
supplies
a
the
in
metal
reducing
statements
the
extraction
oxides
to
is
not
of
true
metals?
metal.
agent.
cheap.
heat
required
for
the
reaction.
SECTION
9
a
C:
Given
Short
part
of
answer
the
questions
metal
reactivity
series:
b
Using
write
sodium
magnesium
zinc
iron
copper
Where
should
hydrogen
be
c
a
full
dissolving
equation
to
show
Using
in
dilute
sulfuric
acid.
the
ionic
dissolving
Why
is
equation
to
show
(3)
one
non-metallic
in
gold
any
acid.
found
as
an
equation
sodium
the
sulfate
The
following
sodium
Steel
is
a
from
to
show
how
reaction
and
a
Why
the
pure
between
magnesium.
of
mixture
are
reacts
(3)
chart
shows
reactions
of
cations
(3)
Cations
P
Q
R
S
iron
Explain.
and
NaOH
iron( II)
(2)
P:
blue
precipitate
green
precipitate
carbon.
of
copper
and
steel
and
bronze
White
precipitate
tin.
R:
i
a,
(1)
mixture
is
it
solution.
S:
Bronze
part
hydroxide.
Q:
b
oxide
hydroxide
Add
Give
a,
iron
element?
v
part
reacts
(3)
with
iv
it
iron
12
Give
from
how
(2)
with
iii
oxide
show
water.
write
Give
to
placed?
Explain.
ii
non-metallic
equation
gold
with
i
one
an
called
red-brown
Excess
precipitate
NaOH
alloys?
Precipitate
does
(1)
not
Cupronickel
ii
What
have
can
be
used
properties
so
that
it
to
should
makes
make
coins.
cupronickel
good
dissolve
coins?
(3)
a
Identify
b
Write
cations
an
ionic
P
,
Q,
R
and
equation
for
S.
R
(4)
with
NaOH.
(3)
10
a
What
iron
b
i
substances
before
What
and
ii
is
it
will
the
be
why
in
contact
with
rust?
(2)
chemical
formula)
Explain
must
of
structure
is
Car
bodies
rusting
i
Describe
i
an
example
be
paint
and
doubly
and
protected
of
ii
the
two
from
iii
Will
if
it
the
is
car
body
deeply
automatically
scratched?
iv
Blocks
of
are
Explain
bolted
to
the
aluminium:
name
of
the
aluminium
(1)
What
is
the
Why
is
chemical
formula
for
oxide?
cryolite
(1)
added
to
aluminium
your
a
(1)
Write
an
equation
during
aluminium
v
(2)
magnesium
is
reaction
rust
answer.
d
What
of
ore?
methods.
(4)
ii
extraction
aluminium
galvanising.
explain
the
ore?
(2)
can
with
In
(2)
oxidation.
c
a
(name
rust?
rusting
13
ship’s
Why
does
by
the
for
the
the
anode
extraction
of
electrolysis
anode
(2)
need
to
be
replaced?
b
In
the
extraction
(2)
of
iron:
hull.
i
i
Explain
how
this
reduces
steel
corrosion.
ii
Why
the
11
must
(2)
there
magnesium
Non-metallic
oxides
be
no
and
are
paint
the
usually
between
steel
hull?
acidic
(1)
Which
three
added
through
blast
ii
Why
raw
materials
the
top
of
are
the
furnace?
is
limestone
furnace?
(3)
used
in
the
blast
(1)
or
neutral.
a
Give
that
two
are
examples
acidic.
of
non-metallic
oxides
(2)
173
Glossary
Alloy
A
A
lattice,
Acid
A
proton
mixture,
of
two
within
or
more
a
metallic
metals
or
C
a
donor.
Calorimeter
mixture
of
one
or
more
metals
with
heat
Acid
anhydride
forms
an
acid
A
when
compound
it
reacts
energy
water.
Carboxylic
Amphoteric
A
substance
which
5.6
rain
due
Rain
to
the
which
has
reaction
a
of
pH
below
act
as
an
acid
or
acidic
a
Catalyst
oxide
An
oxide
up
with
both
acids
and
a
A
salt
A
salt
in
which
only
been
more
hydrogen
partially
metal
in
the
replaced
acid
by
Negative
Catalytic
or
Anode
The
positive
electrode.
vehicle
indicator
compounds
A
mixture
which
coloured
of
the
coloured
changes
thickness
layer
colour
on
process
of
specific
oxide
alkalis
the
The
An
oxide
which
broken
to
of
an
unreactive
surface
of
a
smallest
converter
reduce
the
monoxide
Catalytic
form
a
salt
and
down
particle
by
that
chemical
of
the
reaction.
Part
added
emissions
and
to
of
of
nitrogen
petrol
oxides
engines.
at
cracking
Cracking
using
a
400–500 ºC.
cannot
means.
energy
The
Cathode
of
energy
minimum
particles
economy
mass
molar
of
masses
must
they
negative
electrode.
Cations
required
Positive
ions.
product
of
all
the
100
Centrifugation
The
separation
of
products
from
lighter
particles
using
the
have
Atomic
when
The
water.
heavier
react
end
oxide
metal.
×
Activation
to
the
reacts
molar
amount
speeds
remains
pH.
Atom
with
at
exhausts
catalyst
be
Acidic
but
increasing
over
Atom
a
to
carbon
The
from
or
that
reaction
ions.
has
one
Anodising
compound
for
alkalis.
atoms.
Acid–base
name
the
Anions
replaceable
substance
chemical
unchanged
Acid
Another
which
gases.
reacts
acids
acids.
base.
rainwater
Amphoteric
with
measuring
can
alkanoic
Acid
for
changes.
non-metal.
that
with
Apparatus
a
number
The
number
of
force
caused
by
a
spinning
action.
collide.
protons
in
the
nucleus
of
an
atom.
CFCs
Compounds
of
carbon,
fluorine
Addition
Avogadro
polymerisation
Polymerisation
containing
C = C
a
The
number
of
of
and
chlorine
which
cause
breakdown
of
23
atoms
monomers
constant
in
a
mole
of
atoms
(6
×
10
ozone
into
oxygen.
double
atoms).
bond
to
form
compound
is
a
polymer
and
no
other
Chain
Avogadro’s
made.
conditions
Addition
reaction
A
reaction
in
single
product
is
formed
from
two
reactant
product
is
molecules
and
no
the
temperature
same
and
the
volumes
of
all
gases
pressure,
contain
isomerism
structure
of
Isomerism
the
carbon
where
skeleton
differs.
the
or
Chemical
same
more
of
Under
which
equal
a
law
number
of
properties
Properties
that
molecules.
other
describe
made.
react
how
with
elements
other
and
compounds
substances.
B
Alcohols
Organic
compounds
with
Chlorination
Base
branched
or
containing
unbranched
− OH
the
A
base
which
functional
is
proton
group.
Basic
soluble
in
oxide
acids
Saturated
general
formula
hydrocarbons
C
acids
+
Organic
or
the
− COOH
A
made
from
the
of
of
biological
C = C
double
group
The
containing
gas
of
a
excess
The
air
or
burning
oxygen.
fuel
formed
by
the
two
or
more
A
substance
different
made
atoms
(or
up
of
in
The
that
manure
the
or
other
absence
of
organic
joined
together
by
bonds.
air.
change
takes
of
place
state
when
from
a
liquid
liquid
Polymerisation
types
the
formed
by
of
polymerisation
occurring
monomer
bond
when
two
together
elimination
of
a
small
with
molecule.
atom
from
energy
The
energy
needed
to
Condensation
reaction
A
reaction
the
a
covalent
bond
between
two
where
two
molecules
join
together
an
particular
atoms.
the
elimination
(removal)
of
a
small
alkane.
molecule.
Branched
Allotropes
Different
forms
of
the
chain
hydrocarbons
same
Hydrocarbons
with
carbon
alkyl
side
Condensed
formula
A
structural
element.
groups
coming
off
the
main
chain.
formula
are
Brittle
174
of
ions)
bond.
group
hydrogen
in
at
break
removal
combustion
substance
Condensation
Bond
Alkyl
a
material.
boils.
one
microorganisms.
water.
functional
to
least
chlorine
chains
Boiling
Hydrocarbons
of
harmful
compounds
unbranched
group.
Alkenes
reacts
kill
with
compounds
containing
addition
to
2
breakdown
branched
and
treatment
Compound
2n
Biogas
with
which
salt
H
n
Alkanoic
a
water
Complete
Fuels
decomposition
the
oxide
form
water.
Biofuels
Alkanes
An
to
The
acceptor.
in
with
Alkali
A
chains
Breaks
easily
when
hit.
showing
arranged
in
a
how
the
atoms
molecule
without
with
Glossary
showing
or
triple
the
bonds
apart
from
double
bonds.
Downward
movement
downwards
Condensing
The
change
of
state
to
a
gas
due
to
or
The
liquid
the
pressure
of
Endothermic
reaction
which
energy
absorbs
Energy
Can
be
drawn
into
wires.
profile
showing
the
have
a
low
resistance
to
of
and
axis
Electric
Corrosion
The
gradual
dissolving
metal
and
the
inwards
from
its
amps
charge
×
time
The
in
product
of
bond
A
shared
pair
Enthalpy
series
The
and
reactivity
reaction
pathway
on
the
change
The
of
metals,
with
between
a
heat
energy
chemical
the
its
surroundings
at
reaction
constant
most
pressure.
reactive
Cracking
The
decomposition
of
at
the
molecules
into
a
mixture
Enzymes
and
Rods
which
A
current
to
and
from
Ester
an
of
A
compound
R − COO − R′
regularly
an
repeating
Electrolysis
arrangement
catalysts.
with
the
formula
alkenes.
electrolyte.
lattice
Biological
conduct
of
electric
alkanes
top.
larger
Electrodes
ions
or
molecules
The
decomposition
of
alcohol
formed
with
an
by
the
reaction
alkanoic
of
acid.
a
in
compound
three
the
order
of
of
Crystal
of
vertical
surface.
electrons.
smaller
the
current
seconds.
Electrochemical
alkane
on
axis.
exchanged
Covalent
products
away
in
a
Diagram
content
electricity.
horizontal
of
energy
the
E
passage
diagram
heat
Substances
reactants
that
the
gas.
Ductile
(electrical)
reaction
surroundings.
liquid.
Conductors
A
from
from
another
gas
displacement
of
by
an
electric
Esterification
current.
Making
an
ester
by
the
dimensions.
reaction
Electrolysis
cell
A
container
in
of
an
alcohol
with
an
alkanoic
which
acid.
D
electrolysis
is
carried
out.
Eutrophication
Dehydration
reaction
A
reaction
Electrolyte
A
molten
ionic
to
involving
the
removal
of
water
from
a
or
a
solution
containing
ions
conducts
the
death
result
of
electron
Electrons
which
nitrates
Electrolytic
conduction
not
associated
with
any
particular
movement
of
ions
in
a
liquid
or
when
a
into
potential
difference
is
liquid
lakes
and
A
dirt
substance
from
a
that
removes
material.
Electron
way
of
arrangement
showing
the
A
electrons
Molecules
containing
in
each
electron
rivers.
change
vapour
of
which
state
takes
the
boiling
point
of
a
place
liquid.
shorthand
number
reaction
A
reaction
of
which
Diatomic
and
The
to
Exothermic
stain
as
phosphates
applied.
below
Detergent
and
solution
from
atom.
leading
organisms
The
Evaporation
are
processes
aquatic
electricity.
leaching
Delocalised
of
which
a
compound.
The
compound
shell
of
releases
energy
to
the
an
surroundings.
two
atom
(sometimes
called
the
‘electron
atoms.
configuration’).
F
Diffusion
The
spreading
movement
of
Electron
one
substance
through
another
due
shells
random
movement
of
the
areas
Faraday
to
surrounding
the
Spherical
the
nucleus
which
electric
one
or
more
constant
charge
(of
ions)
The
gain
or
electrons
by
ions
at
the
electrodes
atoms
or
one
of
mole
or
one
mole
of
singly
of
charged
The
negatively
ions.
charged
to
particles
form
quantity
by
loss
Electrons
of
carried
electrons.
electrons
Discharge
The
contain
particles.
outside
the
nucleus
of
an
Feedstock
molecules.
A
material
taken
from
atom.
nature
Displacement
reaction
A
one
type
of
atom
or
ion
another
in
a
one
metal
formula
Shows
how
the
compound
are
less
Element
atoms
and
bonds
in
which
has
Coating
with
a
layer
of
of
the
surface
undergone
is
another,
used
as
slight
the
processing
starting
which
material
for
a
compound.
usually
Displayed
substance
has
of
replaced
a
reaction
Electroplating
where
or
a
only
one
reactive,
A
substance
type
of
chemical
metal.
atom
made
up
which
process.
Fermentation
of
cannot
be
organic
The
materials
by
breakdown
of
microorganisms
arranged.
broken
Dot-and-cross
showing
the
diagram
electronic
A
diagram
arrangement
down
chemical
ions
or
between
bond
the
simpler
by
with
effervescence
heat
energy.
and
the
release
of
formula
Shows
the
simplest
Filters
Equipment
used
to
remove
dust
molecules.
whole
Double
anything
of
Empirical
atoms,
into
reactions.
T
wo
same
covalent
two
bonds
a
number
ratio
of
atoms
or
ions
in
and
particles
power
compound.
from
chemical
plants
and
stations.
atoms.
End
The
point
point
colour
in
(in
acid–base
where
a
an
titration.
titration)
indicator
changes
Filtrate
filter
The
paper
solution
solution
when
are
a
passing
mixture
of
through
solid
a
and
filtered.
175
Glossary
Flue
gas
sulfur
desulfurisation
dioxide
burning
in
fossil
industry
fuels
Removal
arising
containing
of
from
Hard
(substance)
is
easily
not
unit
of
an
ions
in
Shows
ionic
the
substance
which
simplest
Ionisation
to
sulfur.
remove
ratio
water
dissolved
Water
calcium
that
or
salts.
Isotopes
the
distillation
product
that
is
a
of
petroleum
of
neutralisation
mixture
of
change
when
formed
by
one
the
mole
The
reaction
of
of
energy
from
an
needed
atom
or
of
number
an
of
element
protons
with
but
enthalpy
water
an
Atoms
same
different
A
The
electron
contains
magnesium
compound.
Heat
Fraction
energy
an
ion.
Hard
Formula
A
scratched.
numbers
of
neutrons.
is
acid
with
K
hydrocarbons
molar
having
a
limited
range
of
an
alkali
under
standard
conditions.
masses.
Kinetic
Heat
of
reaction
The
enthalpy
particle
particles
Fractional
distillation
A
to
two
liquids
separate
or
more
method
used
with
when
the
shown
molar
in
the
amounts
equation
of
theory
The
idea
that
change
are
in
constant
motion.
reactants
react
to
give
L
different
using
a
boiling
points
distillation
from
each
other
products
under
standard
conditions.
column.
Law
Heat
of
solution
The
enthalpy
a
Freezing
The
change
of
state
from
when
one
mole
of
a
solute
is
of
conservation
chemical
to
solid.
in
a
solvent
to
form
an
reaction,
the
mass
mass
of
In
the
dissolved
products
liquid
of
change
infinitely
is
equal
to
the
mass
of
the
dilute
reactants.
solution
Functional
group
A
group
that
under
standard
conditions.
is
Leaching
characteristic
of
a
given
homologous
Homologous
series
A
group
The
substances
series.
compounds
with
the
same
and
the
same
functional
A
reaction
General
formula
applied
to
all
A
formula
members
of
that
a
can
water
is
added
to
molecular
not
in
A
carbon
and
hydrogen
network
of
reactant
pairs
in
in
The
a
reactant
which
reaction.
Pairs
of
electrons
not
bonding.
atoms.
Lustrous
A
water.
containing
three-
covalent
by
excess
involved
structure
of
product.
Lone
Compounds
Hydrogenation
dimensional
new
series.
only
Giant
a
given
Hydrocarbons
homologous
form
out
pollutants)
where
is
be
soil
Limiting
reaction
or
group.
G
Hydration
(minerals
general
through
formula
washing
of
reaction
Having
a
shiny
surface.
involving
bonds.
the
addition
of
hydrogen
to
a
M
Global
warming
atmosphere
The
caused
by
heating
of
absorption
compound.
the
of
Macromolecules
Hydrolysis
infrared
radiation
by
greenhouse
that
chemistry
reduces
or
A
set
of
eliminates
breaking
down
of
by
use
up
Malleable
and
of
hazardous
substances
manufacture
and
use
of
large
molecules
units.
Can
be
shaped
by
hitting.
concentration
The
number
of
in
Incomplete
the
repeating
I
Mass
generation
of
water.
principles
the
Very
a
made
compound
Green
The
gases.
combustion
Combustion
grams
of
solute
dissolved
in
a
solvent
to
chemical
when
air
or
oxygen
is
3
limiting.
make
1 dm
of
a
solution.
products.
Indicator
Greenhouse
good
and
gases
absorbers
cause
of
global
Gases
infrared
that
See
Acid–base
indicator.
Mass
number
+
number
radiation
Insulators
the
An
atom
or
group
of
atoms
of
in
protons
an
atom.
vertical
columns
in
the
either
a
positive
or
negative
The
change
of
state
from
solid
with
to
The
number
neutrons
Non-conductors.
Melting
periodic
of
warming.
Ion
Groups
The
are
liquid.
charge.
table.
Metallic
Ion-exchange
(resin)
A
bound
ions.
bond
The
ions
attractive
delocalised
replaced
by
different
bond
ions
forces
formed
between
by
the
can
H
be
A
substance
the
containing
when
electrons
and
the
positive
a
ions.
Half
the
equations
oxidation
Equations
and
reduction
showing
solution
containing
ions
flows
through
it.
reactions
Metallic
Ionic
bond
The
strong
force
of
attraction
between
oppositely
mobile
The
addition
of
halogen
electrons
The
movement
through
the
metal
charged
lattice
Halogenation
conduction
of
separately.
when
a
potential
difference
is
ions.
applied.
atoms
to
a
compound
or
substitution
of
Ionic
halogen
atoms
into
a
equation
A
symbol
equation
compound.
Metalloids
that
shows
only
those
ions
which
the
Halogens
The
elements
in
Group
VII.
part
in
a
metals
176
and
lying
non-metals
between
in
the
reaction.
periodic
Ionic
Elements
take
lattice
A
crystal
lattice
of
ions.
table
which
have
properties
of
metals
properties
of
non-metals.
and
some
some
Glossary
Mixture
This
elements
or
consists
of
compounds
two
that
or
more
are
Photochemical
O
not
by
Osmosis
chemically
bonded
The
overall
movement
the
from
molecules
through
a
moles
concentration
of
solute
The
dissolved
number
in
a
of
solvent
to
permeable
membrane
water
a
is
at
higher
Smog
caused
hydrocarbons
car
exhausts,
ozone
and
nitrogen
selectively
oxides
Molar
smog
between
of
together.
water
reaction
from
where
concentration
in
the
presence
of
sunlight.
the
to
Physical
properties
Properties
which
3
make
1 dm
of
a
solution.
where
it
is
at
a
lower
concentration.
do
of
Molar
mole
of
Molar
in
gas
volume
gas
at
mass
r.t.p.
The
The
or
volume
of
one
s.t.p.
mass
of
Oxidation
of
a
substance
moles.
electrons
Oxidation
to
each
show
Mole
The
relative
mass
The
by
a
of
oxygen
or
or
ion
degree
of
A
in
a
substance
Polar
number
generally
or
formula
molecule
positive
amount
partial
negative
Molecules
charge
on
with
one
a
end
compound
charge
on
the
and
a
other.
to
oxidation.
Pollution
Contaminating
materials
(atomic,
mass)
in
grams.
A
full
into
the
natural
environment
Oxidation–reduction
(reactions)
equation
the
given
(earth,
Molecular
on
present.
partial
introduced
molecular
depend
loss
substance.
number
atom
the
gain
not
Reactions
in
air
or
water).
which
symbol
oxidation
and
reduction
occur
together.
Poly(alkene)
Polymer
formed
when
equation.
alkene
Oxidising
Molecular
formula
Shows
of
atoms
of
each
A
substance
electrons
and
gets
that
reduced.
Polyamide
in
one
molecule
Condensation
polymer
particular
containing
element
combine.
the
accepts
number
agent
monomers
of
− NH − CO −
linkages.
a
P
compound.
Paper
Molecular
structure
Structure
to
separate
Molecule
more
same
A
method
or
The
mixture
of
containing
atoms
can
two
be
solubility
the
and
substances
of
their
the
substances
attraction
to
in
on
the
Percentage
and
bond
molecules
together
to
form
which
a
amount
of
maximum
The
conversion
of
the
monomers
to
polymers.
Polymers
Macromolecules
solvent
paper
.
linking
small
polymer
linkages.
different
depending
different.
The
− COO −
Polymerisation
particle
atoms.
Monomers
react
a
molecules.
dissolved
or
A
Condensation
containing
of
used
simple
chromatography
Polyester
at
least
50
made
up
by
monomers.
yield
required
amount
product
of
Polysaccharide
obtained
product
expected
containing
Condensation
− O −
polymer
linkages.
polymer.
×
N
Natural
gas
Fossil
fuel
extracted
100
Position
Periodic
table
elements
in
the
Earth’s
surface
which
group
differs.
so
that
with
Periodicity
oxide
An
oxide
which
react
with
acids
or
Neutralisation
between
of
increasing
most
similar
an
reaction
acid
and
a
The
groups
atomic
contain
properties.
regular
properties
The
base
reaction
to
form
a
periodic
given
group
Precipitate
The
precipitation
reaction.
of
the
occurrence
elements
Precipitation
of
in
in
which
a
solid
obtained
in
a
is
A
reaction
obtained
trend
in
table
have
so
that
similar
elements
in
properties
a
or
a
solutions
of
two
soluble
when
compounds
are
mixed.
properties.
discharge
of
ions
The
water.
Neutron
nucleus
reaction
solid
Preferential
and
Periods
The
of
an
Noble
gas
having
a
neutral
particle
in
the
periodic
The
horizontal
rows
in
discharge
the
anion
table.
configuration
complete
outer
Atoms
shell
of
Permanent
hardness
water
cannot
which
only
during
one
type
of
cation
or
electrolysis.
be
Hardness
removed
Protons
in
particles
by
The
in
positively
the
nucleus
charged
of
an
atom.
boiling.
R
Petroleum
Non-polar
partial
of
atom.
electrons.
of
in
functional
alkalis.
the
no
the
does
similar
salt
Isomerism
of
methane.
Neutral
not
position
is
elements
mainly
of
the
from
number
beneath
Arrangement
order
isomerism
which
(molecule)
charge
positive
and
or
Molecules
where
negative
the
with
centre
charge
is
the
of
A
thick
unbranched,
hydrocarbons
the
Earth’s
pH
scale
liquid
branched
extracted
mixture
and
from
ring
Radioactive
beneath
unstable
isotopes
nuclei,
which
Isotopes
break
with
down.
surface.
Rate
of
reaction
The
change
in
same.
Nucleus
of
an
A
atom
tiny
particle
containing
in
the
protons
centre
and
14
a
used
A
to
solution
scale
show
of
numbers
how
acidic
from
or
0
to
alkaline
concentration
with
time
at
a
of
a
reactant
stated
or
product
temperature.
is.
neutrons.
177
Glossary
Redox
(reaction)
reduction
See
Oxidation–
Sedimentation
(reactions).
usually
in
a
The
settling
of
a
solid,
liquid.
s.t.p.
Standard
pressure
(0 ºC
temperature
and
1
and
atmosphere
pressure).
Reducing
loses
agent
electrons
A
and
substance
gets
which
Separating
oxidised.
used
to
which
Reduction
of
The
electrons
by
loss
a
of
oxygen
or
atomic
atoms
an
mass
of
atom
mass
of
an
of
of
mass
The
naturally
element
the
exactly
on
apparatus
liquids
Strong
densities.
a
acid
completely
The
reducing
effect
the
of
inner
amount
of
electron
Strong
nuclear
completely
scale
felt
isotope
has
Simple
a
units.
by
the
outer
a
distillation
liquid
from
processes
mass
of
one
compound
mass
formula
on
a
The
unit
scale
of
of
a
The
solid
boiling
separation
which
and
involves
of
the
having
the
carbon-12
isotope
the
12
high
a
atom
have
has
a
mass
of
detergents
sulfonates
groups
COO
or
Detergents
groups
other
that
atoms
mass
of
Masses
as
compared
to
Soaps
at
Sodium
long-chain
carbon-12.
molecular
one
formula
with
or
are
a
scale
mass
molecule
where
the
‘head
end’
of
or
potassium
carboxylic
of
a
The
relative
compound
Soft
water
hardly
any
Water
without
an
atom
of
magnesium
the
showing
a
the
way
molecule
the
bonds.
the
isomers
same
Compounds
molecular
salts
structural
formula
but
isotope
has
a
mass
of
formulae.
of
contains
calcium
to
a
The
without
gas,
the
or
direct
of
liquid
a
change
gas
state
to
a
of
a
being
solid,
formed.
or
reaction
A
reaction
in
salts.
one
atom
or
group
of
atoms
exactly
The
number
of
grams
of
replaces
another.
units.
solute
needed
to
form
a
saturated
Suspension
Replaceable
hydrogen
The
hydrogen
solution
per
100
grams
of
solvent
an
acid
which
can
be
replaced
by
or
ammonium
The
solid
curve
A
graph
showing
and
in
which
the
remaining
on
the
a
mass
of
saturated
solute
dissolved
solution
per
to
form
100 grams
on
paper
when
a
of
small
another
small
substance,
particles
settle
standing.
of
Sustainable
filter
in
ion.
the
Residue
mixture
dispersed
a
Solubility
metal
A
used.
particles
in
in
acids.
which
dissolved
Solubility
12
in
the
which
carbon-12
Shows
arranged
Substitution
on
ions
than
solid
Relative
of
molecule.
masses
such
Electrolytes
condensation
the
Soapless
an
units.
standard
ionises
concentration
Sublimation
a
that
condenser.
different
Relative
base
electrolyte.
with
exactly
ionises
solution.
electrolytes
a
Structural
of
that
electrons.
relative
a
where
A
in
Structural
formula
acid
solution.
base
Strong
where
using
Relative
An
in
weighted
occurring
carbon-12
12
of
immiscible
different
Shielding
charge
average
separate
have
Piece
gain
substance.
shells
Relative
funnel
mixture
of
solid
and
solvent
at
different
chemistry
See
Green
temperatures.
chemistry
solution
are
filtered.
Solute
A
substance
that
is
dissolved
in
Synthesis
Ring
hydrocarbons
Hydrocarbons
a
reactions
where
the
carbon
atoms
are
joined
series
which
of
make
chemical
a
specific
in
Solution
a
A
solvent.
A
uniform
mixture
of
two
or
product.
ring.
more
r.t.p.
Room
temperature
and
substances.
pressure.
T
Solvent
(20 ºC
and
1
atmosphere
A
substance
that
dissolves
a
pressure).
solute.
Rusting
Corrosion
of
iron
and
T
emporary
iron
water
Sonorous
alloys
caused
by
the
presence
of
Rings
when
hit
with
a
and
can
be
Hardness
in
removed
by
boiling.
Cracking
using
hard
both
object.
water
hardness
which
Thermal
cracking
oxygen.
high
Spectator
ions
Ions
which
do
not
pressure
and
temperatures
above
take
700 ºC.
part
S
in
a
reaction.
Thermal
Salt
A
compound
formed
when
the
Standard
concentration
decomposition
breakdown
hydrogen
in
an
acid
is
replaced
by
a
concentration
of
1 mol
of
The
A
of
a
compound
when
substance
heated.
3
metal
or
ammonium
ion.
in
of
1 dm
solution
under
standard
conditions.
Saponification
The
hydrolysis
of
Thermometric
in
or
oils
to
form
Standard
soaps.
solution
A
solution
which
has
compounds
with
only
known
accurate
concentration
single
added
specified
temperature
and
is
to
word
for
symbols
Letters
put
after
the
formula
showing
whether
it
as
one
reaction
solution
is
another
.
given
a
solid,
liquid,
gas
or
aqueous
A
amount
method
of
used
substance
to
determine
present
in
a
is
Shielding).
178
recorded
a
shielding
chemical
(see
titration
a
pressure.
Titration
Another
A
of
bonds.
State
Screening
temperature
at
Organic
a
compounds
a
the
which
mixture
Saturated
titration
fats
solution.
volume
of
solution
of
acid
or
alkali.
Glossary
Titre
the
The
initial
final
burette
burette
reading
reading
in
a
minus
titration.
Upward
displacement
movement
of
a
gas
The
upwards
W
due
to
the
Weak
pressure
Triple
bond
between
the
Three
same
covalent
two
of
another
acid
ionises
in
acid
which
only
partially
solution.
atoms.
Weak
V
base
ionises
Volatile
U
Easily
evaporated
at
in
A
base
which
only
partially
solution.
room
temperature.
Unbranched
An
gas.
bonds
Weak
electrolytes
Electrolytes
having
chain
a
hydrocarbons
Hydrocarbons
with
Vulcanisation
Process
used
in
low
concentration
of
ions
in
the
the
electrolyte.
carbon
alkyl
atoms
side
compounds
(in
in
a
chain
without
groups.
Unsaturated
bonds
linked
used
compounds
containing
addition
manufacture
to
make
tyres
the
where
rubber
sulfur
is
harder.
Organic
double
single
to
of
or
triple
bonds).
179
uL
muitetul
17
]062[
rL
muicnerwal
301
0.371
bY
muibretty
07
]952[
oN
muilebon
201
9.861
mT
muiluht
96
]852[
dM
muivelednem
101
3.761
rE
muibre
86
]752[
mF
muimref
001
9.461
oH
muimloh
76
]252[
sE
muinietsnie
99
5.261
yD
muisorpsyd
66
1.252
fC
muinrofilac
89
9.851
bT
muibret
56
1.742
kB
muilekreb
79
3.751
dG
muinilodag
46
1.742
mC
muiruc
69
0.251
uE
muiporue
36
1.342
mA
muicirema
59
4.051
mS
muiramas
26
1.932
uP
muinotulp
49
9.441
mP
muihtemorp
16
0.732
pN
muinutpen
39
2.441
dN
muimydoen
06
0.832
U
muinaru
29
9.041
rP
mu
im
yd
oesa
rp
95
0.132
aP
muinitcatorp
19
eC
muirec
85
0.232
hT
muiroht
09
sedinitcA
85
09
–
–
17
301
sedinahtnaL
*
]172[
sD
muidiri
77
]862[
tM
muirentiem
901
2.091
sO
muimso
67
]772[
sH
muissah
801
muitenhcet
34
2.681
eR
muinehr
57
]462[
hB
muirhob
701
9.59
oM
munedbylom
24
8.381
W
netsgnut
47
]662[
gS
muigrobaes
601
muidanav
32
9.29
bN
muiboin
14
9.081
aT
mulatnat
37
]262[
bD
muinbud
501
9.74
iT
muinatit
22
2.19
rZ
muinocriz
04
5.871
fH
muinfah
27
]162[
fR
0.54
cS
muidnacs
12
9.88
Y
muirtty
93
9.831
*aL
munahtnal
75
]722[
1.04
aC
muiclac
02
6.78
rS
muitnorts
83
3.731
aB
muirab
65
]622[
K
muissatop
91
5.58
bR
muidibur
73
9.231
sC
muiseac
55
]322[
1.041
0.571
gR
87
rI
44
cT
42
V
78
]272[
munitalp
2.291
muinehtur
]89[
muimorhc
9.05
88
97
tP
54
uR
52
rC
98
dlog
1.591
muidohr
1.101
esenagnam
0.25
401
08
uA
64
hR
62
nM
011
yrucrem
0.791
muidallap
9.201
nori
9.45
111
18
gH
74
dP
72
eF
rF
muillaht
6.002
revlis
4.601
tlaboc
8.55
muicnarf
28
lT
84
gA
82
oC
muidar
dael
4.402
muimdac
9.701
lekcin
9.85
muinitca
38
bP
94
dC
92
iN
)8(
)7(
)6(
)5(
)4(
)3(
1.93
muidrofrehtur
htumsib
2.702
muidni
4.211
reppoc
7.85
muitdatsmrad
48
iB
05
nI
03
uC
muinegtneor
muinolop
0.902
nit
8.411
cniz
5.36
detacitnehtua
58
oP
15
nS
13
nZ
aR
enitatsa
]902[
ynomitna
7.811
muillag
4.56
cA
68
tA
25
bS
23
aG
stnemelE
nodar
]012[
muirullet
8.121
muinamreg
7.96
htiw
nR
35
eT
33
eG
cimota
]222[
enidoi
6.721
cinesra
6.27
srebmun
45
I
43
sA
611-211
nonex
9.621
muineles
9.47
evah
eX
53
eS
neeb
3.131
enimorb
0.97
detroper
63
rB
tub
notpyrk
9.97
ton
rK
ylluf
8.38
)9(
cimota
)01(
)notorp(
)11(
rebmun
)21(
11
51
21
61
31
71
41
81
aN
iS
muidos
surohpsohp
1.82
muisengam
ruflus
P
5
eman
I
9.6
muinimula
enirolhc
0.13
norob
evitaler
cimota
cimota
lobmys
ssam
yeK
II
0.9
nocilis
nogra
S
6
B
0.32
1.23
nobrac
8.01
gM
lC
7
C
3.42
5.53
negortin
0.21
lA
rA
8
N
0.72
9.93
negyxo
0.41
1
0.1
ehT
)1(
3
9
O
0.4
0
cidoireP
)2(
4
01
eniroulf
0.61
)31(
iL
F
)41(
muihtil
noen
0.91
)51(
muillyreb
eN
)61(
eB
2.02
)71(
I I I
H
V I
elbaT
negordyh
2
V
fo
muileh
I V
eht
eH
I I V
stnemelE
180
Index
in
A
acid
anhydrides
acid
rain
acid
salts
acidic
acids
as
63
indicators
oxides
58–9,
60–1,
an
and
68
extraction
linkages
ammonia
156
acid-base
metal
amide
59
39,
59,
preparation
60–1
breathalyser
brittle
61,
electrolyte
fertilisers
63
81
bromine
butane
162
of
in
test
123
materials
bromides
63
manufacture
62
145
134
66,
42,
77,
32–3,
150
169
120–1
110–11,
118,
petroleum
164
116
153
C
concentration
of
61,
reactions
72–3
69,
76,
127
cadmium,
electrical
conduction
in
in
80
tests
166–7,
calcium
as
electrolytes
81,
82
ammonium
ion
ammonium
salts
41,
58,
63,
62–3,
140
with
carbonates
with
metals
62,
62,
67,
140,
168
84–5,
139,
63,
66,
amphoteric
oxides
amphoteric
substances
anions
40–1,
82,
hard
oxides
with
sulfites
58,
62,
63,
67,
140
anodes
82–3,
at
reactions
30,
energy
98,
anodising
101
polymerisation
132–3
antacids
83,
hard
30,
reactions
120,
120–1,
122
arsenic,
rusting
alcoholic
in
79,
drinks
atom
89,
rate
in
121,
124–5
122–5,
esterification
toxicity
acid
of
see
of
as
names
112
atomic
and
structures
113
atoms
biofuels
from
mass
also
series
homologous
algae,
see
58,
60–1,
in
72–3
chloride
drying
acid
reactions
127
electrolytes
81,
163,
2,
bonds
salt
preparation
22,
of
24,
26,
calcium
hydroxide
113,
metals
reactions
in
ammonia
in
carbon
homologous
alkanoic
acids
in
lime,
in
sucrose
series
law
nitrate,
58–9,
oxide
120–1,
polymers
group
allotropes
alloys
with
iron
extraction
sulfate
70,
144–5
161
with
168
15,
52–5
concentration
tests
with
168
electrolysis
70–1
88–9
energy
63
changes
titrations
62
104–5
72–3
calorimeters
145
carbon
165
27,
102
44–5,
combustion
119
154
gives
118,
120
134
79,
electrochemical
155
series
85
122
series
6,
7,
and
18
metal
extraction
144
112
structures
from
points
10,
16–17
in
metal
extraction
in
organic
90,
91,
144
113
alcohol
volatility
122
compounds
110
132
of
alkanes
of
halogens
of
non-metals
of
transition
as
118
in
32
reducing
steels
agent
151
147
44
carbon
150
dioxide
27,
39,
59,
62
146–7
146–7,
90,
with
35,
for
166,
in
water
62,
139,
in
34
iron
extraction
preparation
158–9
energy
144
152
8,
in
105
36–9,
rain
water
reactions
46–7
160
producing
and
making
105
alkanoic
acid
140,
141
120,
123
127
148
branched
cracking
156–7
140
breaking
corrosion
gas
167
bonding
oxide
greenhouse
139
bond
tests
aluminium
138
145
of
reactions
metals
148
trends
extraction
in
164
153
114
aluminium
and
agent
123
and
alkyl
drying
113
boiling
and
141
130
boiling
names
30,
emissions
calculations
tests
60–1,
oxides
bleaches
homologous
63
18
54–5
64
barium
biogas
alkenes
soil
128–9
soaps
polymerisation
to
extraction
112
structures
gives
added
48–9
49,
chloride,
biofuels
oxidation
153
170
112
series
in
test
46–7
constant
powder
bauxite
and
dioxide
49
barium
basic
names
140
120
bases
long-chain,
73,
121
119,
126–7,
homologous
50–1,
preparation
26
calcium
baking
118,
160–1
139
69
118–19,
combustion
30,
29
B
alkanes
37
number
22–5,
Avogadro
in
164
in
in
140
153
28
number
Avogadro’s
82
58,
152,
hydrogencarbonate
as
as
31,
agent
calcium
cleans
alkanoic
94–5
144
C
calcium
alkalis
93,
70,
156–7
162,
mass
isotopes
165
64,
149
vitamin
119,
economy
atomic
127
128–9
studies
91
acid
alcohols
152
160–1
91
atmosphere
148
water
64
ascorbic
139
139
141,
90–1
87,
ionic
air
31,
carbonate
168–9
as
addition
160–1
66
59
calcium
addition
of
62
uses
activation
149
131,
salts
in
gases
168
water
insoluble
and
with
of
166
153
calcium
143
138,
167
in
reactions
toxicity
170–1
hydrocarbons
110
combustion
118,
117
naming
114–15
181
Index
fermentation
limewater
as
a
solvent
for
uses
of
64,
gives
with
ion
carbonates
149,
64,
hard
52–3,
tests
of
for
143,
168
127,
140,
acid
acids
also
alkanoic
98–9,
biological
alkanes
118,
of
alkenes
120
of
Group
alcohols
of
alkenes
120
30
70–1,
acids/alkalis
of
75
134
acids
condensation
condensed
enzymes
reaction
formula
129
142
38,
40
115
16–17,
116–17
125
softening
160,
diagrams
bonds
39,
agents
drying
in
152,
153
153
extraction
materials
38–9
110
152,
sucrose
161
37,
displacement
drying
ductile
84–5
74
manufacture
downward
132,
32–3,
111,
water
double
94–7
polymerisation
83
reactions
dot-and-cross
72–3
92,
rum
for
81
61,
rate
in
33
63
formula
distillation
11
numbers
ions
reactivity
organic
10,
154
32,
4–5
displayed
120
8–9,
58,
halogens
for
118
123
reaction
acids
displacement
of
elements
condensation
101
see
II
119,
132,
molecules
discharged
combustion
of
and
126
126
diatomic
123
concentration
group
171
131
44–5,
diffusion
of
of
with
118
alcohols
oxidation
168
test
dibasic
compounds
160
168
carboxylic
see
141,
66
carboxylic
catalysts
144
168
62,
solubility
120
detergents
diamond
of
complete
water
reactions
118,
41
decomposition
and
164
20–1
127
13
combustion
154
combustion
reduction
65,
chloride,
colloids
7
monoxide
carbonate
acid
cobalt
170
of
carbon
citric
168
163
sublimation
test
chromatography
124
test
46,
19
138
111
E
green
chemistry
163,
catalytic
converters
164
catalytic
cracking
164,
165
condensing
6,
7,
16,
17
electric
conductors,
electrical
in
see
117
also
electrical
82–3,
conductors,
90–1
thermal
138,
ions
at
86,
copper
87
90,
138,
144,
36,
82,
centrifugation
19
83,
electrodes
166–7
85,
87,
88,
metallic
tests
for
oxide
74,
conductivity
compounds
isomerism
acid
114
reactions
with
62,
63,
of
state
copper
6–7
sulfate
67,
46,
see
electric
electrolysis
charge
87,
47,
in
properties
9,
as
112
electrolyte
45,
47,
150
34
88
electrochemical
chemical
138
44,
84
trends
charge
81
47
67
non-metals
changes
80,
43,
76
metals
chain
46
31
166
ionic
copper
157
bonds
charge
90
electrical
CFCs
89
147
nuclear
40–1,
88,
40–1
150
and
hydrogen
cations
24
electrolysis
conductivity
on
cathodes
charge
80
81,
series
84–5,
139,
82
142–3
of
metals
of
non-metals
water
139
test
with
171
metal
corrosion
150–1
146–7,
extraction
electrodes
periodic
table
29,
reducing
34–5
90,
82–7,
ion
as
bleach
covalent
79
bonds
38–9,
58,
139,
covalent
140
compounds
40,
41,
of
for
structures
66
cracking
169
44–5,
chloride
chlorine
crude
161
32–3,
at
anodes
in
ionic
see
38
oil
47
cells
arrangement
electron
shells
of
26,
manufacture
as
oxidising
of
see
27
42,
agent
74,
77,
77,
78,
alkanes
with
water
also
bonding
chloride
16,
19,
171
of
155
from
9,
182
149
electrodes
83
in
atoms
23,
in
bonding
22,
25,
36–9,
31
40
indicator
delocalised
65
reaction
123
45,
in
displacement
46,
47,
80
in
electrolysis
in
metals
in
redox
reactions
electrons
45
86–7
67
of
chlorophyll
at
67
118–19
in
for
38
35
metals
density
uses
36–7,
81
151
delocalised
test
24,
lattices
dehydration
sodium
29
29
151
DCPIP
with
23,
44
D
reactions
22,
145
lattices
crystallisation
43
23,
petroleum
electrons
isotopes
82
electron
in
crystal
36
82
80–1,
116
also
cryolite
87
bonds
145
86–7
117
electrolytes
chlorination
90,
43,
75
electrolysis
tests
86–91
extraction
sodium
solubility
82–3,
47
metal
chlorides
144
90–1
91
electrolysis
chlorate(I)
90,
148
30,
water
46,
138,
158
47,
80
150
46,
47
reactions
electroplating
90–1
74,
77
84–5
Index
elements
8,
isotopes
10,
of
ordering
22,
oxidation
empirical
fire
numbers
6–7,
food
75
64,
32,
green
154
desulfurisation
in
93,
103
reactions
Group
5,
70,
71,
79
100,
105
energy
98,
45,
between
molecules
alcohols
122
alkanoic
acids
47
44,
II
Group
156–7
salts
66,
elements
of
VII
groups
62,
138,
decomposition
oxides
47
162–5
gases
elements
soluble
Group
atoms
101
I
nitrate
64
between
70
chemistry
greenhouse
164
33
preservation
vinegar
40
70,
31,
activation
gas
forces
68,
endothermic
extinguishers
fluorine
23
13
point
energy
28–35
flue
formula
emulsions
end
24,
26
62,
69
30–1,
141
66
elements
28,
143
141
see
halogens
29
126
H
and
green
chemistry
163,
165
and
boiling
points
158–9
haem
see
also
enthalpy
changes
between
particles
2,
149
3
haemoglobin
energy
levels
see
electron
shells
and
change
of
state
half
energy
profile
diagrams
100,
101
in
ionic
lattices
equations
changes
100–5
in
metallic
bonding
32–3,
impact
162–5
formula
unit
detergents
131
formulae
40–1,
48,
of
of
leaching
metals
see
also
fossil
160
fuels
see
149
pollution
156,
also
66
118–19
110–11
halogens
and
32–3,
151
164
alkane
reactions
118–19
alkene
reactions
120–1
petroleum
fractional
crystallisation
fractional
distillation
15
displacement
enzymes
79,
99,
149
green
chemistry
163,
165
of
petroleum
redox
50–1,
59
in
rum
manufacture
reactions
61
fractions
linkages
130,
135
freezing
6,
128–9,
130
freezing
points
127,
128–9,
130
fruit
65,
39,
110,
116,
118
fuels
116–17,
156,
of
acid
reactions
in
vinegar
ethanol
61,
127,
81,
123,
126
alkanes
129
fossil
124,
as
biofuels
64
122,
125
materials
138,
conductors
energy
esterification
123,
39,
110,
156,
groups
in
also
enthalpy
polymer
111,
of
neutralisation
heat
of
reaction
102,
103
heat
of
solution
102,
103,
gives
3,
4–5,
6,
bond
132,
131,
in
colloids
in
electrolysis
ionic
100,
constant
163,
filtrate
63,
11,
88,
89
165
64,
99,
155,
124–5
157
sucrose
in
water
acid
an
58,
electrolyte
carbonate
89
hydroxide
170–1
equations
metals
51
oxide
152–3
reaction
of
rates
92,
in
94
the
59,
165
61
81
reactions
reactions
reactions
reactions
93,
68,
31,
62,
stomach
hydrogen
12
giant
ionic
giant
molecular
94–5
73,
62,
140
139
63,
140
64
22,
23,
124,
extraction
purification
18
161
electrodes
uses
of
42
44–5,
26
85,
87,
in
metal
in
organic
series
150
145,
154
extraction
144,
compounds
numbers
50,
54,
74,
75,
145
110
76
150
84–5
hydrogenation
redox
84
82
displacement
135
80,
86
58–9,
reactions
149
47,
47
36,
oxidation
157
linkages
44–5,
ions
structures
135,
cathodes
electrochemical
gas
112
structures
warming
graphite
16
natural
formula
glycosidic
13,
at
154
also
general
glucose
16
10–11,
in
as
13
solutions
global
164
11,
filtration
hydrochloric
54–5
105
see
filters
49,
157
F
fertilisers
for
101
uses
fermentation
125
116–17,
18
making
feedstock
122,
110,
133
in
Faraday
121,
157
reactions
cataracts
112
123
and
eye
series
hydrocarbons
6–7
law
preparation
exothermic
105
112
122
in
evaporation
104
164
111,
hydration
2,
identifying
eutrophication
102–3,
120
manufacture
from
changes
heat
129
dehydration
ethanol
150
6–7
127
Avogadro’s
ethanol
138,
119
fuels
functional
gases
ethene
45
165
G
reactions
of
transfer
homologous
in
42,
146
157
see
ethanoic
35
79
heat
ethane
32,
160
10
heat,
esters
131,
7
metals
esterification
points
water
116–17
hardness
ester
32–3
74
125
hard
equilibrium
reactions
116–17
melting
equations
reactions
17
as
in
83
169
40
halogenation
of
86,
46
solubility
environmental
74,
42–3
halides
enthalpy
149
6–7
121
151
154
183
Index
reactions
forming
acid/metal
30,
31,
sodium/ethanol
replaceable
test
for
58,
139
126,
iron,
oxides
in
123
rust
isomers
63
hydrogen
chloride
hydrogen
peroxide
4–5,
39,
139
of
79,
mass
52–3,
90,
144
148
in
48,
49,
50,
electrolysis
rates
114–15
isotopes
170
of
reduction
139
from
93,
subatomic
26–7
171
52–5
88–9
94–5
particles
mass
concentration
mass
number
24,
24
71
25,
26
K
93,
153
see
kinetic
decomposition
in
redox
particle
theory
also
melting
77,
mass
4
99
reactions
atomic
78
6,
melting
7
points
10,
47
L
hydrogen
sulfide,
toxicity
of
156
lactic
hydrogenation
acid
lattices
ion
62,
129,
42–3,
ion
see
metal
group
32,
44,
150
35
146
of
mass
138,
149
50
138,
144,
147,
metal
carbonates
metal
hydroxides
see
carbonates
acid
salts
of
58,
reactions
63,
decomposition
166,
bromide
lead
nitrate
140,
140
141,
143
167
formation
lead
127,
66
122
for
61
149
hydroxides
tests
138
42,
160
insoluble
hydroxyl
47,
82
lead
hydroxides
46,
conservation
130
41,
non-metals
mercury
of
46,
44–5
160–1
leaching
hydroxide
30,
halogens
law
hydrolysis
of
41
metallic
hydrogencarbonates
metals
64
121
hydrogencarbonate
of
81,
82,
86,
62,
139
88–9
I
solubility
immiscible
liquids
21
tests
limestone
incomplete
combustion
60–1,
electrodes
test
metal
nitrates
metal
oxides
see
reactant
58,
2–3,
4,
reactions
in
colloids
in
ionic
34,
80,
13
equations
preparation
solutions
corrosion
32–3,
74,
22,
23,
litmus
molecular
crystals
tests
things/life
and
resin
160,
110,
metal
36–7,
metals
compounds
also
149
acids
metallic
bonds
metallic
conduction
40–1,
pairs
conductivity
of
mass
materials
29,
34
138
80–1
metals
formula
80
38
42–3
lustrous
relative
46–7
64–5
metalloids
molten,
90
oxides
47
lone
ionic
extraction
159
161
natural
bonding
141
66
46
see
ion-exchange
139,
of
60–1
in
21,
salts
44
living
solution
30,
25
78
insoluble
ionic
148
12
formation
in
67
51
169
lithium
iodine
140
127
81
in
66,
acids
66
in
iodides
63,
156–7
salt
insulators
62,
6–7
alkanoic
salts
141
53
acid
radiation
insoluble
nitrates
168
85
liquids
infrared
166
160
68
limiting
inert
144,
with
118
limewater
indicators
66
169
46–7,
138–49
48
basic
oxides
of
62
M
ionic
equations
51
cation
macromolecules
ionic
lattices
tests
132
42–3
conduction
magnesium
ionic
166–7
structures
42–3,
in
46,
in
31,
59,
chlorophyll
of
25,
hard
water
131,
metal
reactions
on
36,
31,
62,
139,
by
80,
acid
82–3,
ionic
compounds
34,
water
in
equations
metals
tests
for
reactions
properties
11,
30,
35,
147,
139
magnesium
carbonate
magnesium
hydroxide
magnesium
oxide
64,
30,
with
acids
with
alkanoic
37,
43,
84–5
hydrogen
58,
126
63
127
of
30,
139,
solubility
of
trends
Group
46,
47
151
sulfate
5,
70,
maleic
79,
in
II
30–1
161
149
methane
anhydride
38,
118,
119
164
148
greenhouse
malleable
166,
materials
46,
gas
156–7
138
167
in
manganese(IV)
184
67,
acids
151
magnesium
for
62,
160
64
144–5
haemoglobin
40
138
151
51
formation
tests
142,
166–9
139,
rusting
139,
46
extraction
in
46,
84
replace
iron
36–7,
34
36
reactions
ionic
29,
74
physical
31,
table
85–7
displacement
of
144–5
81
chlorine
formation
91,
126
periodic
electrolysis
90,
151
in
conduction
in
142–3
160–1
40–1
alkanoic
in
reactivity
75
extraction
charge
144
31
in
2,
90,
90
and
ions
84–5
149
extraction
energy
series
61
extraction
ionisation
80
47
electrochemical
ionisation
47,
138
oxide
99,
153
petroleum
116
Index
methanoic
acid
occurrence
mixtures
in
81,
of
126
64,
10–11,
molar
concentration
molar
gas
molar
mass
volume
molasses
19,
formula
molecular
structures
2,
48–9,
monomers
chemistry
solvents
see
27,
132,
50–1
110,
44–5,
115
47
48
133,
135
of
solvents
of
alcohols
of
alkanes
118
of
alkenes
121
also
83
metals
30,
ionic
reduction
numbers
75–6,
alkane
combustion
alkene
oxidation
plastics
118
graphite
44–5
32–3
42–3
112
118
121,
waste
121
150
and
122
alkanoic
83
29
compounds
alkanes
78
reactions
11,
138
compounds
organic
alcohols
41,
156
9,
46,
non-metals
122
155
smog
halogens
of
of
properties
diamond
123
oxidation–reduction
134,
physical
catalyst
uses
photochemical
44
74–9,
acid
phosphorus,
110–35
43,
of
see
phosphoric
64–5
acids
non-polar
65,
oxidation
70–3
61,
5
oxidation
38–9,
52–5,
also
osmosis
40,
59,
alkanoic
organic
125
equations
acids
also
organic
70–1
54
molecular
moles
20–1
52–3
molecular
molecules
see
16–17
chromatography
49,
organic
127
acids
132,
from
126
133
157
N
indicators
natural
gas
neutral
for
see
also
oxides
58,
see
also
58,
acid/hydroxide
68–70,
acids
reactions
in
62,
22,
24,
25,
58,
pollution
oxides
156,
tests
for
agents
77–8,
ion
123,
and
151
see
79
green
also
140–1,
39,
manganate(VII)
acid
anodes
163
impact
121
132
polyamides
134,
polyesters
135,
135
164,
87,
89,
poly(ethene)
91
132,
165
133
gives
numbers
141,
75,
168
polymerisation
polymers
76
132–3,
132–5,
164,
134
165
61
tests
reactions
50,
54,
polysaccharides
150–1
135
169
50–1,
63,
metals
30,
139,
142
polystyrene
133
76
redox
reactions
74,
poly(tetrafluoroethene)
151
133
141
in
nitrogen
39,
nitrogen,
oxides
63,
64,
rusting
of
62,
140,
engines
from
nitrates
156,
tests
for
141,
for
170
of
154
potassium
in
dichromate(VI)
sulfur
dioxide
layer
119,
157
potassium
hydroxide
potassium
iodide
168–9
test
171
paper
chromatography
configuration
cation
36,
37
particles
2–3,
acidic
29
29,
oxides
in
34,
of
tests
150–7
62
33,
bonding
in
covalent
36–9
diffusion
4,
reactions
92,
in
solutions
12
98,
in
oxidation
in
in
sulfur
compounds
non-polar
molecules
non-polar
solvents
40
47
158,
periodic
159
yield
table
periodicity
51,
in
46,
47
periods
also
organic
solvents
31
22,
24,
27
28–35,
28,
75,
116,
118,
hardness
petroleum
116–17,
propene
110,
120,
121
from
133,
to
number
fossil
22,
165
24
161
also
atomic
number
156
transfer
58–9
165
22,
23,
24
fuels
pure
pH
85
121
180
protons
also
ions
29
permanent
see
66
of
34
alternatives
135
reaction
discharge
110,
proton
134,
171
166
propane
see
charge
test
66,
162
proton
nuclear
4
123
12–13
polymers
solubility
121,
22–5
suspensions
percentage
78,
dioxide
preferential
ionic
93
101
precipitation
41
78,
5
in
subatomic
compounds
167
77,
manganate(VII)
precipitates
in
72–3
6–7
potassium
non-metals
68,
21
20–1
reactions
gases
123
171
P
in
gas
test
143
nitrates
dioxide
114
164
ozone
nitrogen
isomerism
156
uses
from
position
148
155
test
nylon
162,
66
with
nuclei
chemistry
143
reactions
see
46
168–9
of
58,
halide
78,
153
oxidation
in
in
160
environmental
poly(alkene)
33
decomposition
solubility
noble
157,
26
at
noble
126
solubility
157
decomposition
nitrites
solvents,
41
oxygen
in
122,
140
potassium
nitric
158
volatility
127
halogens
nitrates
polar
150–1
metal
chlorate(I)
ion
and
reactions
72–3
oxidising
alkanoic
redox
62
neutralisation
nitrate
molecules
116
oxides
neutrons
polar
65
substances
10
60–1
purification
of
metals
purification
of
water
90
O
pH
orbits,
electron
scale
60
23
phosphates,
pollution
by
131,
157
PVC
see
also
161
electron
133
shells
185
Index
silicates,
Q
qualitative
analysis
uses
silicon(IV)
166–71
silver
R
76,
84,
insoluble
radioactive
rate
of
reaction
reactivity
of
isotopes
II
the
and
thermal
see
see
oxidation;
as
food
in
iron(III)
see
also
79
in
oxide
52–3,
90,
90,
144
91
oxidation
formula
relative
masses
relative
molecular
replaceable
mass
mass
24,
48
48
hydrogen
48
58,
63
16
temperature
110
and
pressure
49,
54
rum
49,
54
with
water
79,
125
123,
35,
chloride
sodium
carbonate
sodium
chloride
from
9,
62,
160,
of
83,
81,
preservation
elements
ionic
bonds
in
5,
14–15
ethoxide
sodium
hydrogencarbonate
sodium
hydroxide
hydrolysis
123
43,
64,
139
temperature
132,
of
65
63,
140
51
reactions
2–3,
6–7
with
30,
139
147
names
112–13
54
strong
acids
strong
bases
strong
61,
81
electrolytes
61
81
structural
formula
40,
structural
isomers
114
42–3,
111
44–7
110
subatomic
130
127,
and
135
matter
organic
129,
72
72
54
symbols
structures
166
81
62,
standard
s.t.p.
151
159
51
solution
stem
70
67,
of
tests
158,
ions
159
104
concentration
steel
sodium
electrolyte
capacity
standard
steam,
36–7
curve
water
states
86–7
9,
heat
138
120
standard
state
82
from
118,
enthalpy
starch
161
43
47
44
materials
pressure
16–17
electrolyte
reactions
67
46,
43,
20–1
163
159
spectator
139
42,
of
specific
of
151
139
70
food
in
161
130
cation
chemistry
flames
and
126,
benzoate
as
148
160,
36
sodium
in
manufacture
rusting
acids
solubility
green
sooty
resins
53,
with
as
in
sonorous
138
bonds
soaps
chromatography
water
131
163
in
organic
160
electrolysis
48
mass
hydrocarbons
r.t.p.
ionic
119
dioxide
non-polar
90,
distillation
26,
169
157
reactions
151
141,
detergents
sodium
extraction
relative
room
in
66
145
23,
12
alkanes
155
carbon
of
88,
130–1,
sodium
145,
144
ion-exchange
83
atomic
ring
series
118
relative
residue
141
reduction
77–8,
74–9,
metal
soaps
123
alkanes
of
soapless
34
83
preservation
reduction
of
74–9,
agents
ethanol
in
31
table
144,
solvents
155
117,
salts
nitrate
cancer
slag
electrochemical
also
skin
decomposition
reactions
reducing
101
142–3
periodic
also
silver
elements
and
redox
92–9,
84–5,
Group
27
of
oxide
particles
sublimation
22–5
7
S
sodium
salt
(sodium
chloride)
in
salts
food
sodium
salts
nitrite
alkanoic
acids
126,
127,
food
141
substitution
sucrose
70
reaction
18–19,
119
46
electrolytes
81,
formation
58,
preparing
62–3,
66–7,
thiosulfate
68,
water
2,
rates
from
12,
93,
95,
98
fermentation
as
160
149
of
124
polysaccharides
solubility
13
of
state
14–15,
6,
sulfate
7
46,
ion
sulfates
47
chromatography
110,
135
46
41
58,
21
and
hard
139,
140,
water
168
161
compounds
42–3
solubility
of
66
118
molecular
crystals
tests
44
for
168
79,
168
31
polar
sedimentation
separating
molecules
funnels
to
of
mixtures
for
for
curves
12,
12,
14–15
11,
44,
reactions
sulfur
154
with
dioxide
and
14–15
53,
59,
151
164,
acid
rain
168
156
16–17
liquids
of
70–1
in
food
preservation
21
conduction
settlement
sulfur
21
concentration
immiscible
sulfites
20–1
solutions
distillation
126
66
10–11
solutes
chromatography
predict
21
solubility
separation
122,
12
rules
in
test
80–1
for
171
161
as
shielding
18–19
18–19,
130
compounds
screening
5,
93
ionic
saturated
cane
sugars
69
and
saponification
71
70
solubility
sampling,
131,
3,
change
64,
70,
140
solids
of
sugar
141
82
soft
uses
140,
preservation
129
sodium
mixtures
10,
12,
21
sulfuric
acid
58,
61
31
separating
186
140,
63
in
as
63,
preservation
58
acid
of
nitrate
5
16–17,
21
as
an
electrolyte
81
79
Index
anodising
catalysis
as
with
by
drying
agent
electrolysis
in
ethanol
reactions
titres
91
toxic
128
of
transition
153
tribasic
86
dehydration
62,
69,
68–9
123
reaction
substances
triple
118,
metals
acids
bonds
40,
58,
39,
149,
156
trends
reactions
138
alkanoic
63
acid
carbonate
110
58,
68
127
127
combustion
hydroxide
140
34–5
forming
118,
50–1,
120,
140,
123
141
U
with
halides
169
with
hydroxides
oxide
unbranched
63,
area
and
rate
indicator
symbol
compounds
110,
reactions
chemistry
equations
134,
54
135
120
12–13
displacement
50,
68
polymerisation
upward
sustainable
60,
97
unsaturated
suspensions
140
110
oxygen/hydrogen
universal
surface
hydrocarbons
72–3
with
metals
30,
139
152
162
rusting
50–1
in
148
self-ionisation
of
82
V
synthesis
121,
162,
163
solubility
vaporising
6,
42–3
7
states
vinegar
in
of
matter
of
2
64
T
vapour
vitamin
Teflon
C
65,
test
171
127
133
volatility
temperature
density
of
water
acids
weak
bases
61,
reaction
rate
of
gas
49,
92,
electrolysis
weak
electrolytes
54–5
98
reaction
solubility
rates
terylene
from
92,
124
94–5
14–15
vulcanisation
temporary
81
89
winemaking
and
81
61
158
in
and
weak
126
6–7
volume
and
122,
hardness
154
160–1
Y
135
yeast,
fermentation
with
124–5
W
tetrafluoroethene
133
washing
soda
160
Z
thermal
conduction
138,
150
waste
149,
157,
163
zinc
thermal
cracking
144,
147,
biogas
from
119
reactions
thermal
decomposition
8,
9,
39,
141,
reducing
hydrolysis
titrations
70,
solution
from
76,
138,
in
osmosis
167
58–9
zinc
chloride
zinc
hydroxide
81,
zinc
oxide
84,
140
5
141,
166,
167
147
pollution
titrations
166,
103
in
tin
for
71
ionisation
of
78
129
tests
heat
139
agent
143
in
thermometric
85,
158–61
as
reactivity
84,
140–1
water
and
149
117
68–71,
93,
of
157
62,
140,
141
103
purification
of
161
187
Acknowledgements
The
authors
permission
and
to
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Howard
4.1.1
Emilio
Science
Science
6.1.1
Image,
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Segre
Visual
Library;
Photo
6.4.1
Library;
Photo
Llc/Alamy;
David
9.1.1
iStockphoto;
Library;
R.
Eye
Martyn
Davies/Alamy;
Library;
Norris;
F
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18.2.2
Andrew
13.6.3
David
effort
the
has
been
made
necessary
F
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Library;
7.1.1
7.5.2
Photo
Editorial
Norris;
Martyn
7.8.2
Andrew
Shutterstock;
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Shutterstock;
Danita
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Photo
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Photo
67photo/Alamy;
Photography/Science
188
Norris;
Library;
Photography/Science
been
Martyn
Chillmaid/Science
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make
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Ubiquitous/Alamy;
Shutterstock;
following
Institute
Novosti/Science
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5.5.3
7.4.1
Chillmaid/Science
thank
Sciencephotos/Alamy;
foodcollection.com/Alamy;
Lambert
to
Archives/American
4.2.1
Library;
Mauro
like
2.3.3
Photography/Science
Science
Library;
would
photographs:
Davies/Alamy;
Photo
Lambert
publishers
reproduce
17.2.1
19.1.1
Andrew
Photo
Roger
Andrew
Lambert
Library.
to
trace
overlooked
arrangements
the
the
at
copyright
publisher
the
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will
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but
if
any
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to
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