Unit 1 – Matter
Classification of Matter
Properties of Matter
DO NOW
What is Tyndall effect?
Write three examples of an element.
Write three examples of a compound.
Agenda
‘Do Now’
Continue our discussion on matter
A. Matter Flowchart
MATTER
yes
MIXTURE
yes
Is the composition
uniform?
Homogeneous
Mixture
(solution)
PURE SUBSTANCE
no
Heterogeneous
Mixture
Colloids
no
Can it be physically
separated?
yes
Can it be chemically
decomposed?
Compound
Suspensions
no
Element
Pure Substances
1. Element
composed of identical atoms
EX: copper wire, aluminum foil
Pure Substances
2. Compound
composed of 2 or more
elements in a fixed ratio
properties differ from those
of individual elements
EX: table salt (NaCl)
Another example..
Water
What is the chemical formula for
water?
This has a 2:1 ratio
It is an example of a pure substance
AND also a compound.
Mixtures
Variable combination of 2 or more pure
substances.
Heterogeneous
uneven distribution
(suspensions & colloids)
Homogeneous
even distribution
( solutions)
Orange Juice
With pulp?
Without pulp?
Mixtures
1. Solution
homogeneous
very small particles
no Tyndall effect
particles don’t settle
EX: rubbing alcohol
Tyndall Effect
Mixtures
2. Colloid
heterogeneous
medium-sized particles
Tyndall effect
particles don’t settle
EX: milk
The Tyndall
Effect
Colloids scatter
light, making a
beam visible.
Solutions do not
scatter light.
Which glass
contains a colloid?
colloid
solution
Mixtures
3. Suspension
heterogeneous
large particles – can see
Tyndall effect
particles settle
(needs to be shaken)
EX: fresh-squeezed
lemonade
Mixtures
Examples:
jello
colloid
muddy water
suspension
Fog
colloid
saltwater
solution
Italian salad
dressing
suspension
Mixtures vs. Compounds
Components may be
Components are in
in any proportion
Individual
components retain
their own identities
Components may be
separated physically
When mixture is
formed there is little
to no evidence of a
reaction
fixed proportions
Individual
components lose their
identities, new set of
properties result
Components may be
separated only
chemically
When compound is
formed there is
evidence of a reaction
Physical Separation
Techniques
Difference in Densities (density
column – some objects float in others)
Filtration (separate solids from liquids)
Magnetism
Chromatography
Distillation (separation by boiling
points)
Evaporation (separate solids and
liquids)
Density
Filtration
Magnetism
Evaporation
Separation of a Mixture
The constituents of the mixture retain their
identity and may be separated by physical
means.
Separation of a Mixture
The components of dyes
such as ink may be
separated by paper
chromatography.
PROBLEM
This morning someone left me a ransom
note in black ink and they stole Pickles.
I have a few suspects, I need you all to help
me find out who is responsible:
Landlord: A
Neighbor: B
Mailman: C
Ex-girlfriend: D
Sister: E
Separation of a Mixture
Distillation
Types of Properties
Physical
Chemical
Properties that
describe the
substance itself,
rather than
describing how it
can change
Example: boiling
point, color, size
Properties that
describe the
substances ability
to undergo
changes that
transform it into
other substances
Example: charcoal
has the ability to
burn in air
Types of Physical Properties
Extensive properties depend on the amount
of matter that is present.
Volume
Mass
Energy Content (think Calories!)
Intensive properties do not depend on the
amount of matter present.
Melting point
Boiling point
Density
Changes in Matter
Physical Change
Chemical Change
Change in form or
state of matter
without altering
chemical
composition
Examples: slicing a
banana, boiling
water, dissolving
sugar
Changing substance
into new substance
by reorganizing
atoms…chemical
bonds are made or
broken
Examples: burning,
rusting, copper
turns green
5 Indicators of a chemical
change
Color Change
Light emitted (glow sticks, candle
burning)
Temperature change (happens on its
own – you don’t supply heat)
Precipitate forms (solid from 2
liquids)
Gas production (you see bubbles)
Three Phases
Solids
Definite
shape/definite
volume
Molecules are
tightly packed, but
can still move
slightly
Most Dense state
of matter (because
particles are the
closest)
Liquids
Definite volume/no
definite shape
(takes the shape of
its container)
Fluid – because it
“flows”
Particles are not as
close as solids, but
are more dense
than gases
Gases
No definite shape
or volume
Least dense of the
3 states of matter
because the
particles are far
apart
Which state of matter are
they?
Phase
Differences
Solid – definite volume and shape; particles packed
in fixed positions.
Liquid – definite volume but indefinite shape;
particles close together but not in fixed positions
Gas – neither definite volume nor definite shape;
particles are at great distances from one another
Phase Changes
Freezing (liquid to solid)
Melting (solid to liquid)
Evaporation (liquid to gas)
Condensation (gas to liquid)
Sublimation (solid to gas)
Deposition (gas to solid)
**** Phase changes are PHYSICAL
changes!!!!
Dry Ice
What is dry ice?
Process when you are making dry
ice?
Group up
As a group, come up with example of
these phase changes that occurs in
your everyday life:
Freezing
Melting
Condensation
Evaporation