Year 10 Chemistry
Elements
and the
Periodic Table
Copyright : C S Dobson 2011
Elements and the Periodic Table
Revision: Elements and Compounds
Elements
1
Complete the notes below on elements.
Atoms are the (b) .................... blocks of (m) .......................... . A substance is
an (e) ...................... if it is (p) ........................ (only one type of (a) ..................).
This means an element cannot be (b).................... down (chemically) into
anything (s) .................... . There are over 100 different e).................. known to
humans and these are organised on the (P) ........................ (T) ..................... .
All (m) .................... is made up of these (e)....................... . There are (t).............
different groups of elements based on their (c) characteristics:
i)
2
(M) ....................... and
ii)
(N) ............................. .
Name the common metals and nonmetals you need to know.
Metals: (Li) ............................. (Na) .............................. (Mg) ..........................
(Al) ....................... (K) ........................ (Ca) ..................... (Ni) ....................
(Cu) ..................... (Zn) ...................... (Ag) ..................... (Au) ..................
(Hg) ..................... (Pb) ..................... (U) ........................ (Fe) ...................
Nonmetals: (H) ............................ (He) .......................... (C) ...........................
(N) ......................
(O) .....................
(F) .......................
(Ne) ...................
(P) ....................... (S) .......................
(Cl) .....................
(Ar) ....................
(Br) ...................... (I) ........................ Compounds
3
Complete the notes below on compounds.
A (c) ....................... is a (p)................ substance made up of (t) ........... or more
different (e) ................... joined together (c) .................... . A compound can
only be (b) .................... down into simpler substances by (c) ..........................
methods but not (p) ..................... methods. The properties of a compound
4
are (d) ............................ to the (e) ..................... that form it.
Name three common compounds.
(i) ..........................................................
(ii) ..................................................
(iii) .........................................................
Copyright : C S Dobson 2011
Elements and the Periodic Table
Revision:Solutions

Solution is a term commonly used in science to describe a liquid which
has a solid dissolved in it.
5
When scientists discuss solutions they do not use the terms liquid and solid.
Rewrite the above definition using the correct terms ; solvent and solute.
...........................................................................................................................................
...........................................................................................................................................
6
What name is given to the dissolved solid in a solution? ..................................
7
What name is given to the liquid in a solution? .................................
8
List the components of the following solutions.
i)
Solution: Sea water
solute..................... solvent.......................
ii)
Solution: Cup of coffee
solute..................... solvent.......................

Solutions can have different amounts of solute dissolved in a given
volume. Those with a lot of solute, per unit volume, are called
concentrated solutions. Those with a small amount of solute, per unit
volume, are called dilute solutions.
9
Compare the following diagrams and describe the solutions as either
concentrated or dilute.
i)
+
ii)
=
+
iii)
Solution
Solvent
Solute
=
Solution
Solvent
Solute
=
+
Solution
Solvent
Solute
iv)
+
Solute
=
Solvent
Copyright : C S Dobson 2011
Solution
Elements and the Periodic Table
Revision:
10
Atomic structure
Complete the notes on atomic structure and sub-atomic particles below.
All matter is made up of (s) ....................... particles called (a) ........................ . They
are the (s) ...................... particles of an element that can (e) ...................... . Atoms are
(s) ...... small they cannot be seen. 10000000000000 would fit into a full (s) ................ .
Each element is a different type of (a) ........................ . Atoms are typically drawn as
(c) ............................. but are actually spherical.
Scientists have discovered that (a) ................... are made up of (t) .....................
(s) ..........- ....................... particles. They have named the sub-atomic particles
(e) ........................... , (p) .............................. and (n) ............................... .
An atom has a (s) ..................... central region called the (n) ............................ .
Inside the nucleus are found the (p) ........................ and (n) ............................. .
The electrons move (a) .............................. the nucleus in (s) ............................. .
Draw and label a
diagram of an atom
showing the position
of the sub-atomic
particles.
The masses of the sub atomic (p) .......................... are very (s) .......................... .
Scientists have given them a (r) ...................... mass by comparing them to the
(h) ....................... atom. Hydrogen has a relative (m) ................... of (o) ................. .
Protons and (n) ....................... have a relative mass of (o) .................... . Electrons
have a much (s) ........................... mass and it takes ...................... electrons to have
the (s) .................. mass as one (p) ...................... . Some sub-atomic (p) ......................
are charged. Neutrons have (n) ............ charge and so are (n) ........................ ,
(p) ........................ have a single (p) ........................ charge. Electrons have a
single (n) ......................... charge which is the (s) ....................... size as the
charge on a proton.
Copyright : C S Dobson 2011
Elements and the Periodic Table
11
Complete the table below.
Particle
Symbol
Mass
Charge
Proton
Neutron
Electron
An atom is electrically (n) ............................ because the number of
(p)......................... (+) (e) ..................... the number of (e) ......................... (-).
Revision:
12
Electron Configuration
Complete the notes on electron configuration below.
Different elements have (d) ....................... chemical properties eg. (r) .......................,
colour, melting and (b) ......................... (p) ......................... . It is the (n) .......................
and arrangement of (e) ......................... in an atom which determines its properties.
Electrons move around the (n) ....................... of an atom in fixed (s) ..........................
The electrons are arranged in a special way, in a series of shells which are drawn
as (c) ......................... surrounding the (n) .......................... The shell which is
(c) .......................... to the nucleus is shell number (o) ................... . The next closest
shell is (s) ......................... number (t) ......................... and so on. The shell which is
(f) ......................... away from the nucleus is called the (o) ......................... shell.
There are rules for how (e) .........................are placed in (s) .......................... These
rules apply to the (f) ......................... (e) ......................... elements only.
i)
Each shell has a (m) .........................number of (e) .........................it can hold.
Shell one - (t) .........................electrons
Shell two - (e) .........................electrons
Shell three - (e) .........................electrons although 8 is stable
ii)
Electrons fill the shell (c) ........................ to the nucleus first, when this shell is
(f) ................, electrons then fill the (s) ......................... shell and so on.
Copyright : C S Dobson 2011
Elements and the Periodic Table
iii)
Shells are (n) ......................... present if they do not contain electrons.
The (m) ......................... number of electrons a shell can contain is calculated using
the formula ......................... where n is the number of the (s) ......................... .
Shell four can hold a maximum of ...............................
Shell five can hold a maximum of ...............................
The arrangement of (e) .........................in the (s) .........................of an atom are
called the electron (c) ................................
The electron configuration of an atom can be represented in two ways:
i)
eg.
as a (d) .........................
Potassium (K)
ii)
as a series of (n) ..........................
Diagram
Series of Numbers
atomic number = 19
13
proton number
= 19
electron number
= 19
19P
2, 8, 8, 1
Following the example above to complete the electron configurations of the
following atoms.
Lithium
(........)
atomic number
........
proton number
........
electron number ........
Silicon
(........)
atomic number
........
proton number
........
electron number ........
Calcium
(........)
atomic number
........
proton number
........
electron number ........
Copyright : C S Dobson 2011
Elements and the Periodic Table
14
Complete the notes on valence electrons.
The (e) ...................... in the (o) ...................... most shell are called the (o) .................
(s) .............. electrons or (v) ..................... electrons. The (n) ................... of valency
electrons in an (a) ............... determines the (c) ......................... properties of an
(e) ......................... .
15
Complete the table below.
Symbol
Element
Atomic
number
Electron
configuration
Valency
electrons
Number
of shells
H
Li
O
Mg
Si
P
Ar
Ca
Copyright : C S Dobson 2011
Elements and the Periodic Table
Periodic Table
16
Complete the sentences below describing the importance of the Periodic Table.
Scientists have found that (e) ......................... can be grouped according
to their (c) ........................... properties.
A (t) ............................. is used to show these (g) ........................... and is called the
(P) ................... (T) .....................
The table is organized into (r) ................. and (c) ......................... .
The (c) ......................... number represents the number of (v) ..........................
(e) .............................. .
The (r) ........... number represents the number of (s) ...................... an atom has.
All of the (e) ............................ known to humans are placed in this (t) ....................
17
Complete the sentences below describing how elements are placed in the Periodic Table.
i)
Each element is given a number, this number is the number of
(p).......................... the atom has in its (n).......................... and is given the
name (a).......................... number. Elements are placed in the table in (o).......................... of their proton (n).......................... .
ii)
The table is divided into (s).......................... rows each given a number. This
number is called the (P).......................... . The Period refers to the number of
(s)........................ of (e)........................ an element has. Elements in the same
iii)
Period have the (s).......................... number of (s)..................................
The Table has (e)........................ numbered columns, called
(G)........................ . The Groups are numbered from (I)......... to .(e)........ .
The Group number indicates the same as the number of (o)..........................
(s).......................... (e).......................... the atom contains in that group.
Elements in the same Group have the (s).......................... number of
(o).......................... (s).......................... (e)........................... Elements in the same group also have(s).......................... chemical properties.
iv)
The elements between Groups II and III are the (t)..........................
(e).......................... . They are all (m)......................... with (h)..........................
densities and melting points. They produce (c) ..........................................
(s) ...................................... .
Copyright : C S Dobson 2011
Elements and the Periodic Table
18
What are the columns in the Periodic Table called?
...............................
19
What are the rows in the Periodic Table called?
...............................
20
Complete the notes on families of elements?
It is the (n).................... of outershell electrons that determine the general
(c).................... characteristic of an (e) ...................... . This means that the elements
in a particular (G).................. will all have similar chemical (p) ...................... as they
have the same number of (v)......................... electrons.
There are a number of Groups that have special names.
Group one are known as the (a)......................... (m)........................
Group two are known as the (a)......................... (e)........................
Group seven are known as the (h).........................
Group eight are known as the (n)......................... (g)........................ .
21
Why is hydrogen sometimes placed in the centre of the Periodic Table?
...........................................................................................................................................
22
Complete the notes on the Group eight elements.
Group (e)..................... elements need special mention as (a) ............ these elements
have a (f) ......................... (o) ...................... (s) ............................ . They are given the
special name of (N) ......................... (G) ......................... . All these elements are
(i) ...................., this means they do not (r) ................... with other (e) ............................ .
Copyright : C S Dobson 2011
Elements and the Periodic Table
Revision:
23
Nuclide Notation
Complete the notes on nuclide notation.
Nuclide notation is used to represent the what is in an atom’s (n) ........................ .
An element is defined by the number of (p) ...................... in it’s (n) ......................... .
The (n) ...................... of protons found in an atoms (n) ........................... is called
the (a) ......................... (n) ............................ (symbol Z) .
Atoms are (n) ......................... , which means the number of (p) ...........................
equals the number of (e) ........................ . Therefore the (a) ...........................
number in atoms equals the (e) ......................... number. The number of
sub-atomic particles in the nucleus is called the (m) ....................... number
(symbol A) . The mass number (e) ..................... the number of (p) ........................
plus (n) .......................... found in the nucleus. Scientists represent an atom using
the (n) ......................... (n) ........................... . The nuclide notation follows the
pattern below.
24
(m) .......................... number
A
(a) .......................... number
Z
X
(S) ......................... of
the element
Complete the table on nuclide notation.
Atom
Mass
number
Atomic
number
Number
electron
Number
protons
Number
neutrons
11
B
5
42
Ca
20
40
56
18
27
31
35
42
Copyright : C S Dobson 2011
Elements and the Periodic Table
45
Revision:Isotopes
25
Complete the notes on isotopes
An element will have (a) ................... that have the same (p) ....................... number
but different mass (n) ......................... . This is because they have (d) ....................
numbers of (n) ............................. . Atoms with the (s) ...................... proton number
but (d) ................................... neutron numbers are (i) ................................. of the
same (e) ............................... .
26
Complete the table below showing the common isotopes of three elements.
Nuclide
Notation
Element
Protons
Mass Number
Hydrogen
1
1
Neutrons
1
1
3
17
20
35
Carbon
18
6
6
27
1
14
Complete the notes on relative atomic mass.
The mass of atoms are extremely (s)....................... . This makes giving a value in (g).......................
very inconvienient. Instead it is given as a (r)......................... mass by comparing it to the mass of
a (C) .......................... 12 atom, which is said to have a mass of ............................. units.
It is further complicated by the different (i) ................................. that exist for an (e).......................... .
Scientists have found that the (p) ................................. of each isotope is the (s)...................... through
out the (w)....................... . So the (r) ............................ atomic (m)............................ for a given element
is calculated as an (a) ................................ mass of the atoms of the element. It takes into account
the relative (p) ............................ of each isotope.
Naturally occurring silver is 51.84% silver-107 and 48.16% silver-109.
When calculated, the relative atomic mass of silver is = 107.96
Copyright : C S Dobson 2011
Elements and the Periodic Table
28
Use the selection of atoms shown to find the relative atomic mass for chlorine. Use
the table provided to help you organise your information.
35
Cl
17
35
Cl
17
37
Cl
17
37
Cl
17
35
Cl
17
35
Cl
17
35
Cl
17
35
Cl
17
35
Cl
17
37
Cl
17
37
Cl
17
35
Cl
17
35
Cl
17
35
Cl
17
37
Cl
17
35
Cl
17
35
Cl
17
Isotope
37
Cl
17
35
Cl
17
35
Cl
17
Tally
35
Cl
17
Frequency
Copyright : C S Dobson 2011
35
Cl
17
35
Cl
17
35
Cl
17
37
Cl
17
37
Cl
17
37
Cl
17
35
Cl
17
35
Cl
17
37
Cl
17
35
Cl
17
35
Cl
17
35
Cl
17
35
Cl
17
35
Cl
17
35
Cl
17
35
Cl
17
35
Cl
17
37
Cl
17
35
Cl
17
35
Cl
17
MassCumulative
Mass
number
35
Cl
17
Relative
Atomic mass
Elements and the Periodic Table
Reactivity 1

Reactivity refers to how vigorously an element will react with other substances.
29
Complete the notes on the reactivity of elements.
Reactivity is determined by how (e) ................................. elements gain or lose
(v) ................................. (e) ................................. .
An elements (a) ................................. for valence electrons is related to:
i) the number of (p) ................................. in the nucleus
ii) the (d) ........................... valence electrons are from the (n) .............................
iii) the amount of (s) ........................... caused by inner shell (e) .............................
(M) ............................ have a low (a) .............................. for valence electrons and
(r) ...................... increases as the attraction of valence electrons (d) ..................... .
The reactivity of metals (i) ....................... going down a (G) ........................, due to
more (s) .........................., and is greatest in Group (o) ................... metals, due to a
greater (d) ........................... of electrons from the (n) .............................
(N) ......................... have a high (a) .......................... for valence (e) ........................
and reactivity increases as the (a) ............................. of valence electrons
(i) ............................ .
The (r) ........................... of nonmetals (i) ........................... going (u) ........... a Group,
due to (l) ........................... screening, and is greatest in Group (s) ............................
nonmetals ((h) .................................), due to the (s) ................................. distance of
(e) ........................... from the nucleus.
Copyright : C S Dobson 2011
Elements and the Periodic Table
Reactivity 2

Atoms are neutral in charge. This means the number of protons equals the
number of electrons.
⇑
The atoms of most elements do not exist singularly but instead are joined with
other atoms.
30
i)
Name of the Group of elements which exist as single atoms? ...............................
ii)
What is the term for an element that exists as a single atom? ...........................
iii)
What term is used for the reactivity of this Group?
iv)
List 3 such elements and write down their electronic configuration.
Element ..............................
Electronic Configuration
(v)
What do you notice about the outer shells of each of these elements?
...................................................................................................................................

Elements which are monatomic gases are said to be stable.
31
What is meant by the term stable? ......................................................................................

The noble gases are stable because they have a stable configuration. This means
their outer shells are full.
⇑
⇑
⇑
Other elements do not have full outershells and so do not have a stable configuration.
Atoms which do not have a stable configuration are said to be unstable.
There are two ways that unstable atoms can become stable :
(i)
lose or gain electrons
(ii)
share electrons
Both methods involve atoms reacting with each other.
Chemical reactions take place because atoms want a stable configuration.
Copyright : C S Dobson 2011
Elements and the Periodic Table
Atoms and Electron Configuration
1
2
3
4
5
6
7
8
9
10
12
11
13
15
14
16
17
18
Across
1
5
7
8
11
14
15
16
17
18
Number of protons and neutrons in the
nucleus of an atom .(7,6)
Negatively charged particle found in an
atom.
Another term for nucleon number.(4,6)
A particle found in the nucleus of an atom
that has no charge.
A way of showing the proton number and
the nucleon (mass) number of an atom.(7,8)
The term for the elements found on the
left hand side of the periodic table.
Atoms having the same number of protons
but different numbers of neutrons.
The arrangement of electrons around the
nucleus of an atom.
The region around the nucleus of atoms
where electrons are found.
Another term for atomic number.(6,6)
Down
1
2
3
4
6
8
9
10
11
12
13
The term for the elements found on the
righthand side of the periodic table.(3,5)
Two or more different atoms (elements)
joined chemically.
Two or more substances mixed together but
not chemically joined together. Can be
separated physically.
The term for the number of protons in the
nucleus of an atom.(6,6)
The positively charged particle in the nucleus.
No charge.
Electrons that are found in the outer shell
are called ........... electrons.
The dense centre of the atom containing
protons and neutrons.
The type of charge found on an electron
A substance with all atoms having the same
atomic number.
The type of charge found on a proton.
Copyright : C S Dobson 2011
Elements and the Periodic Table
Year 10 Chemistry
Topic 1B
Bonding
Mr 007
Copyright : C S Dobson 2011
Elements and the Periodic Table
Forming Ions : Gaining or Losing Electrons

Ions are formed when an atom creates a stable configuration. A stable
configuration is obtained when the outer shell is full.
⇑
Atoms can obtain a full outer shell by either
(i)
filling their existing outershell by gaining electrons,
ii)
losing all outershell electrons.
⇑
⇑
When all outer electrons are lost, the shell below becomes the new outer shell which is full.
eg.
(i)
Atoms can either gain or lose electrons to become stable. This depends on how
many electrons are in the outershell. The choice which has the lowest movement
of electrons, takes place.
Magnesium (Electronic structure 2,8,2: has 2 electrons in the outer shell.)
trons
lec
se 2 e
lo
Lose 2 electrons: 2, 8 (full)
Mg
The least movement
Note that the ion is smaller
Mg
gain
(ii)
6 ele
ctron
Gain 6 electrons: 2, 8, 8 (Full)
Mg
s
Too many electrons moving
Oxygen (Electronic structure 2,6: has 6 electrons in the outer shell.)
2
gain
ns
o
r
t
c
e
el
O
Gain 2 electrons: 2, 8 (full)
The least movement
Note that the ion remains the same size
O
lose
6 ele
ctron
s
O
Copyright : C S Dobson 2011
Lose 6 electrons: 2 (Full)
Too many electrons moving
Elements and the Periodic Table
1
Complete the table below:
Element
Configuration
sodium
2, 8, 1
Method to get a full outer shell
Number of
Number of
electrons to gain electrons to lose
What
actually
happens
needs to gain 7 e
loses 1 e
needs to lose 1 e
nitrogen
chlorine
calcium
sulphur

When an atom changes the number of electrons to get a stable configuration
the number of protons and electrons are no longer equal. The atom therefore be
comes charged and is no longer called an atom.
2
What is the name given to a charged atom? ......................................
Determining Charge

Not all ions have the same charge. An ion’s charge is calculated by substracting
the number of electrons from the number of protons.
e.g. (i)
Magnesium
Protons
Electrons
Atom
Ion
12
12
12
10
The charge on a magnesium ion is +2 (one electron cancels one protons charge)
12 protons = +p +p +p +p +p +p +p +p +p +p +p +p
10 electrons = -e -e -e -e -e -e -e -e -e -e
Resulting charge = 0 0 0 0 0 0 0 0 0 0 +1 +1
= +2
Result = charge of +2 written as Mg ++ or Mg2+
3
Complete the drawing to show the formation of a magnesium ion.
.......
.......
.......
Copyright : C S Dobson 2011
Elements and the Periodic Table
eg. (ii)
Oxygen : has 8 protons and as an ion 10 electrons (2,8)
The charge on an oxygen ion is -2
4
8 protons =+p +p +p +p +p +p +p +p
10 electrons = -e -e -e -e -e -e -e -e -e -e
Resulting charge = 0 0 0 0 0 0 0 0 -1 -1 = -2
Result = charge of -2 written as O - -or O 2Complete the drawing to show the formation of an oxygen ion .
.......
.......

.......
When an ionic configuration is drawn, it is enclosed in square brackets with its
charge on the top right hand corner
5
Complete the drawings to show the formation of
(i) Aluminium ion
.......
.......
.......
(ii) Sulphide ion
.......
(iii) Chloride ion
.......
Copyright : C S Dobson 2011
Elements and the Periodic Table
6
Complete the table below. (M = metal; NM = Nonmetal)
Element
Symbol M/NM
Protons
Magnesium
Mg
Metal
12
Configuration
Atom
Ion
2,8,2
2,8
Electrons
Lost/Gained
Loses 2
Charge as
ion
Mg++
Aluminium
Sodium
Lithium
Potassium
Calcium
Oxygen
Nitrogen
Fluorine
Sulphur
Chlorine
Phosphorus
7
Complete the notes below by referring to the information in question 6.
1.
All metals (l) ........................... electrons to reach a (s) ...........................
(c) ........................... . When an atom loses (e) ........................... it becomes
(p) ........................ charged. All metals become (p) ........................ charged
(i) ........................... .
2.
All non metals (g) ........................... (e) ........................... to reach a stable
configuration. When an (a) ........................... gains electrons it becomes
(n) ........................... charged. All non metals become (n) ...........................
charged (i) ........................... .
Copyright : C S Dobson 2011
Elements and the Periodic Table

⇑
IONIC BONDING
An atom cannot become an ion without the help of another atom.
Ions are formed when one atom gives up electrons and another atom takes them
in. This is called electron transfer.
⇑
⇑
Electron transfer involves i) Metals losing and ii) Non metals gaining electrons.
8
What name is given to : i) Positive ions ........................ ii) Negative ions ........................
Electron transfer creates a positive ion and a negative ion.
9
i)
Complete the drawing showing
electron transfer between sodium
and chlorine atoms . Note: Normally
only the outershell of each atom
and ion are drawn.
.......
.......
......
......
......
.......
ii)
Complete electron transfer diagrams below for
a) aluminium nitrideb) calcium oxide
......
......
......
......
......
......
......
Complete the following notes on ionic bonding.
Oppositely (c) ...................... ions are (a) ....................... to each other by a strong
force called an (e) ...................... (f) ....................... . This force of attraction keeps
the ions (t) ..................... and the bonds formed are known as (i) ...................
bond.
_
+
metal
ion
opposite charges attract
><
10
......
......
......
......
......
^
non metal
ion
electrostatic force (ionic bond)
The compounds formed by (i) ........................... (b) ........................... are not just
(s) ........................... pairs as shown above. Each (i) ........................... attracts a
number of (o) ........................... charged particles (a) ........................... it.
Copyright : C S Dobson 2011
Elements and the Periodic Table

Ionic compounds do not form
molecules but a giant ionic lattice.
11
Draw a diagram showing the lattice
of sodium chloride in the box opposite.

⇑
All electrons lost by one atom must be taken in by other atoms.
12
Complete the transfer diagram showing the formation of calcium chloride.
Some atoms will therefore need more than one other atom to become an ion.
e.g. Calcium with a configuration of 2,8,8,2 needs to transfer 2 electrons. If
chlorine is receiving the electrons (2,8,7), it can only take in 1 electron.
Thus 2 chlorine atoms will be needed to complete the formation of a
calcium ion.
.....
.....
.......
13
.......
.......
.......
.......
.....
.......
Construct transfer diagrams similar to 12 to show how the compounds are formed.
(i) magnesium fluoride
(ii) aluminium oxide
Copyright : C S Dobson 2011
Elements and the Periodic Table
Chemical Formulae - Ionic

The Ionic formula of a substance has:
i)
the symbols of the elements it contains.
ii)
numbers which show the ratio of the elements present.
⇑
The number to the bottom right of each element symbol is the relative number of
atoms of that element present.
⇑
14
If there is no number, then there is one of that element.
List the type and number of elements present from the formula given.
Eg. Ammonium Chloride
NH4Cl
Name and number of each element: H = Hydrogen – 2 atoms
S = Sulphur
­­ – 1 atom
O = Oxygen
– 4 atoms
1.
Sodium Chloride NaCl
Name and number of each element:
2.
Magnesium Chloride MgCl2
Name and number of each element:

If brackets are used, the number to the bottom right of the brackets is the number
of sets of atoms inside the bracket, eg. (CO3)2 means 2 sets of CO3 = 2 carbon and
6 oxygen.
15
List the type and number of elements present in the following compounds.
1.
Aluminium Sulphate
Al2 (SO4) 3
Name and number of each element:
2.
Ammonium Sulphate
(NH4)2SO4
Name and number of each element:
3.
Calcium Nitrate
Ca(NO3)2
Name and number of each element:
Copyright : C S Dobson 2011
Elements and the Periodic Table

⇑
Determining Ionic Formula
The formulae for ionic compounds are determined by the charges found on each ion.
Rules for calculating ionic formulae.
i) When the number of positive charges on one ion is the same as the negative charges
on the other ion (balanced) the formula is written as having one of each ion.
eg. Magnesium Oxide
Charge on the magnesium ion
= +2 Balanced
Charge on the oxide ion
= –2
As these two ions are balanced the formula is MgO (one of each)
}
ii) If the charges are not balanced the formula is calculated by crossing over the
number for each charge.
eg. Calcium Chloride
Charge on the calcium ion = +2
Unbalanced
Charge on the chloride ion = –1
As the charges of the ions are unbalanced the formula is determined by crossing over.
Ca 2 1 x calcium
The formula is CaCl2
}
Cl 1
16
>
>2 x chlorine
Complete the table of common ions given below.
IonSymbolIonSymbol
Hydrogen ionSodium ion
Lithium ionPotassium ion
Iodide ionSulphide ion
Magnesium ionCalcium ion
Chloride ionOxide ion
Iron (II) ionAluminium ion
Iron (III) ionFluoride ion
Nitride ionBromide ion
Silver ionZinc ion
Ammonium ionCopper (ll) ion
Nitrate ionCarbonate ion
Sulphate ion
Hydroxide ion
Phosphate ionLead (lV) ion
Note : Ions in bold script are those that cannot be worked out from the Periodic Table
17
The name of nonmetal ions end in what suffix? ..........................
18
What is a polyatomic ion? ................................................................................................................
....................................................................................................................................................................
Copyright : C S Dobson 2011
Elements and the Periodic Table
19
Work out the chemical formula of the following.
i)
sodium chloride
ii)
aluminium oxide
iii)
zinc nitrate
iv)
ammonium sulphate
v)
magnesium oxide
vi)
calcium sulphate
vii) potassium oxide
viii)
magnesium carbonate
ix)
iron (II) sulphate
x)
sodium flouride
xi)
ammonium carbonate
xii)
silver nitrate
xiii) ammonium hydroxide
xiv)
copper (ll) hydroxide
xv) lead chloride
xvi)
calcium phosphate
xvii) iron (III) hydroxide
xviii) iron (II) hydroxide
xix) zinc sulphate
xx)
xxi) aluminium iodide
xxii) zinc sulphide
xxiii)lead (lV) nitrate
xxiv) lead (lV) nitride
20
ammonium phosphate
Make up and name 8 chemical formula mot listed above from the ion table.
Copyright : C S Dobson 2011
Elements and the Periodic Table
Covalent bonding

⇑
⇑
When a nonmetal reacts with another nonmetal, electron transfer cannot occur.
14
Complete the notes and diagram below explaining how hydrogen atoms bond together.
Nonmetal atoms must gain electrons to obtain a stable configuration.
When nonmetals react with each other electrons are shared.
When two hydrogen atoms (r) ........................... with each other they both need to
(g) ................... one (e) .................... . Each hydrogen atom allows its (e) ...................
to be shared by the other. The two (s) ....................... electrons form a pair called a
(c) ........................... (b) ........................... . The result is that each (a) ...........................
has two electrons in its (o) ........................... (s) ........................... and thus a stable
(c) ........................... . The outer shells of each atom (o) ........................... so
that sharing can occur. These atoms are therefore joined or (b) ...........................
together. The bond is called a (c) ........................... (b) ........................... .
............................
.......
.......
............................
<
............................
.......
.......

There are two rules that need to be remembered when drawing covalent bonds.
1.
The electrons of one atom are drawn as dots and the electrons of the
other, crosses.
2.
Only outershell electrons should be included in the diagram.
⇑
⇑
15
This type of diagram is known as a dot / cross diagram.
Covalent molecules are not drawn inside brackets.
Draw dot / cross diagrams showing the formation of a single covalent bond for :
(i) fluorine gas
.......
............................
.......
<
.......
.......
............................
............................
Copyright : C S Dobson 2011
..............
Elements and the Periodic Table
(ii) chlorine gas
.......
............................
.......
<
.......
.......
............................
............................
..............

Sometimes more than one pair of electron need to be shared to achieve a stable
configuration.
E.g. Oxygen :
Oxygen (2,6) needs to gain two electrons to be stable.
Two electron pairs are shared between the two oxygen atoms.
Therefore two covalent bonds are formed.
16 Complete the diagram showing the formation of a double covalent bond to form a
molecule of oxygen gas.
.......
............................
.......
<
.......
17
.......
............................
..............
Complete the dot/cross diagram for nitrogen gas.
.......
............................
.......
<
.......

............................
.......
............................
............................
..............
When covalent bonds are formed between two different non metals elements
either :
1.
They are able to share the same number of electrons and so only one of
each atom is needed. e.g. Hydrogen chloride.
18
Complete the dot/cross diagram for the formation of hydrogen chloride.
.......
............................
.......
<
.......
............................
............................
..............
.......
Copyright : C S Dobson 2011
Elements and the Periodic Table
OR
2.
They need to share different numbers of electrons. In these cases
there may need to be more than one of each atom involved in sharing
e.g. carbon dioxide.
19
Complete the notes and diagram for the formation of covalent bonding in carbon dioxide.
Carbon (2,4) needs to share (f) ...... of it’s electrons.
Oxygen (2,6) needs to share (t) ...... of it’s electrons.
.......
Using only one (o) ...................... atom carbon will not
therefore share another two (e) .......................... with a
.......
<
(t) ................. pairs of electrons are shared. Carbon must
<
achieve a (s) ........................... (c) ........................... , as only
.......
............................
............................
second (o) .................. atom. This gives a combined
total of (f) ........................... shared (p) ...........................
............................
of electrons which carbon requires.
...........................
Molecules

⇑
⇑
20
When nonmetal atoms form covalent bonds, they are only joined to the atoms
they are sharing electrons with. This means that a unit of the substance is formed.
The unit for a particular substance has the same number and type of elements
each time it is formed.
The units of a substance are known as molecules.
The chemical formula of a covalent substance indicates the type and number of
elements present in a single molecule (unit).
Complete the table below.
Substance
Formula
Oxygen gas
O2
Elements present
Number of atoms
of each element
HCl
H 2O
CO2
Cl2
CH4
NH3
Copyright : C S Dobson 2011
Elements and the Periodic Table
21
22
Draw dot \ cross diagrams to show the bonding in the following covalent molecules.
You will need to work out how many of each element is needed.
i)
water (H & O)
ii)
ammonia (N & H)
iii)
fluorine gas (just F)
iv)
methane (C & H)
v)
phosphorus trichloride (P & Cl)
vi)
ethane (2 C with single bond & H)
Complete the summary table comparing ionic to covalent substances.
Characterstics
Ionic
Covalent
Type of elements
(metal or nonmetal)
Structure formed
What happens to form
the bond
Copyright : C S Dobson 2011
Elements and the Periodic Table
Bonding
1
2
3
4
5
6
7
14
15
8
9
10
11
12
13
16
17
18
ACROSS
5.
6.
9.
10.
11.
13.
16.
17.
18.
Clues
DOWN
A bond formed by sharing electrons
between two non-metals.
This is an atom that has become
charged.
A measure of how easily electricity
flows through an object.
This is a bond formed between two
oppositely charged ions.
This happens when an ionic compound
is formed. (8,8)
Elements forming negative ions. (5,8)
A unit of a covalent substance.
The liquid form of a substance.
A solid that will not dissolve in a
liquid is ................ .
1.
2.
3.
4.
7.
8.
10.
12.
14.
15.
The charge found on an ion having
more electrons than protons.
It is formed by the sharing of electrons
between two different non-metals. (8,8)
This happens in a molecule when a
covalent bond is formed. (8,7)
When the number of protons is greater
than the number of electrons in an ion,
the charge is .............. .
Elements forming positive ions.
Obtained by subtracting the number
of positives (protons) from the number
of negatives (electrons) in an ion.
Formed between metallic ions and
non-metallic ions. (5,8)
A solid that will dissolve in a liquid
is ................ .
A liquid with another substance
dissolved in it.
A liquid is said to be ............ if it turns
into a gas at a low temperature.
Copyright : C S Dobson 2011
Elements and the Periodic Table
Properties of Ionic and Covalent substances

Ionic and covalent compounds have different properties. This means the type of
bonding present in a substance can usually be deduced by comparing its
properties with those of ionic and covalent compounds.

Complete Practical 2 : Properties of Ionic and Covalent Compounds page 42
Complete the notes on the properties of ionic and covalent substances.
26
Melting and boiling points
Ionic compounds have very (s) .................... forces of attraction between (i) ................ .
This means a (l) ......................... amount of energy is needed to (b) ..........................
them apart. Covalent substances normally form (m) ........................... and these
have a (w) ............... force of attraction between them. This means a (s) ................
amount of energy is needed to break the molecules (a) ....................... . The more
(e) .................. used to break a substance down, the (h) ....................... the melting
and (b) ..................... points. Ionic (c) ........................ therefore have (h) ..................
melting and boiling points while covalent substances have (l) .................. melting
and boiling points. A substance is volatile when it changes into a (g) .....................
easily at (l) ........................... temperatures. As (c) ........................... substances do
this, they are said to be (v) ...........................
Solubility
Most ionic compounds (d) ..................... readily in water releasing their (i) ...............
but are insoluble in organic (s) ....................... . Most covalent substances (d) ........
(n) .......... dissolve in water.
Electrical conductivity
Both covalent and ionic compounds (d) ........ (n) ......... conduct electricity in the
solid (s) ........................ . When an ionic compound is melted (in a (l) ...................... or
molten state ) or is dissolved in water (forming a (s) ...................... ) (i) ..................
are released. These ions allow ionic compounds to (c) ........................... electricity
as a liquid or in (c) ........................... .
Covalent compounds do not contain (s) ........................... and so cannot conduct
electricity as a (l) ........................... or in (s) ........................... .
Copyright : C S Dobson 2011
Elements and the Periodic Table
Practical 2 : Properties of Covalent and

Ionic Substances

Aim : To discover the properties of ionic and covalent substances.
Equipment : Bunsen
Test tubes Test tube rack
Samples
Conductivity kit
Procedure :
Melting / Boiling points
1.
Collect the samples of 6 substances listed in the table below.
2.
Classify each sample as having either ionic or covalent bonds. Record your results.
3.
Look at each sample and describe its state at room temperature. Record your observations.
4.
Place a small amount of each solid sample in a test tube and heat it gently with a
bunsen. Record how easily the sample melted.
Solubility
5.
Test each sample for its solubility in water by placing a small amount of the
substance into a test tube with 4 cm of water. Shake vigorously.
Record whether the substance has dissolved or not.
Electrical conductivity
6.
Use the conductivity kit to determine whether the sample conducts electricity as
a solid. Record your results.
7.
Heat the samples which melted and test them in their molten state to determine if
they conduct electricity. Record your results.
8.
Dissolve those samples which are soluble and test the resultant solutions to
determine if they conduct electricity. Record your results.
Substance Bonding
Volatility
State
mp.
bp.
Solubility
Water
Electrical conductivity
Organic
Sulphur
Yes
Wax
Yes
Sugar
sulphate
Sodium
chloride
Potassium
iodide
Molten
Yes
(C6H12O6)
Magnesium
Solid
(1123OC) Decom.
No
Yes
(801OC) (1413 OC)
No
Yes
(681OC) (1323OC)
No
Yes
Copyright : C S Dobson 2011
Elements and the Periodic Table
Solution
Conclusion :
1
Study the results you have gathered. Summarise your findings in the table below.
Property
Ionic substances
Covalent substances
melting point
boiling point
Solubility
Conducts electricity
solid
molten
solution
Copyright : C S Dobson 2011
Elements and the Periodic Table
Chemistry: Ions in Chemical Formulae
Write the correct formula for the compound formed by each of the following pairs of ions.
1. Na1+
F1–1. ______________________
2. K1+
S2– 2. ______________________
3. Ni2+
SO42–3. ______________________
4. Al3+
O2–4. ______________________
5. Ca2+
OH1–5. ______________________
6. NH41+
P3–6. ______________________
7. Cu1+
NO31–7. ______________________
8. Cu2+
NO31–8. ______________________
9. Pb4+
O2–9. ______________________
10. Li1+
CO32–10. ______________________
For each of the following compounds an X has replaced an ion, write…
A) determine the charge of each ions in the compound , and
B) the number of each ion in one molecule of that compound.
11. X I211. ______________________
12. Na2 X12. ______________________
13. Ag X13. ______________________
14. X F214. ______________________
15. X3PO415. ______________________
16. X SO416. ______________________
17. MgX217. ______________________
18. NH4 X18. ______________________
19. K X19. ______________________
20. Na2 X20. ______________________
Copyright : C S Dobson 2011
Elements and the Periodic Table
Chemical Formulae
Complete the Table by combining the ions matched to the box.
Ions
Chloride
Cl1-
Carbonate
CO32-
Nitrate
NO31-
Sulfide
S2-
Hydroxide
OH1-
Sulfate
SO42-
Aluminum
Al3+
Ammonium
NH41+
Calcium
Ca2+
Copper (I)
Cu+1
Copper (ll)
Cu2+
Hydrogen
H+1
Iron (II)
Fe2+
Iron (III)
Fe3+
Lead (ll)
Pb2+
Lead (lV)
Pb4+
Magnesium
Mg2+
Potassium
K+1
Silver
Ag+1
Sodium
Na1+
Copyright : C S Dobson 2011
Elements and the Periodic Table
Phosphate
PO43-
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Elements and the Periodic Table
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Elements and the Periodic Table
Copyright : C S Dobson 2011
Elements and the Periodic Table
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Elements and the Periodic Table
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Elements and the Periodic Table
Copyright : C S Dobson 2011
Elements and the Periodic Table