MKS@Chemistry Module Form 4 Complete Set

mohd faisol mansor/chemistry form 4/chapter 3

Example 3
1. Construct balanced chemical equations:

a) Magnesium react with oxygen will produce magnesium oxide.

b) Sodium metal react with chlorine gas will produce sodium
chloride.

c) Potassium oxide react with water will produce potassium
hydroxide.

d) Lithium metal react with water will produce lithium hydroxide
and hydrogen gas.

e) Zinc metal react with water will produce zinc oxide and
hydrogen gas.

f) Calcium carbonate react with hydrochloric acid will produce
calcium chloride, water and carbon dioxide.

g) Hydrochloric acid react with sodium hydroxide will produce
sodium chloride and water.

h) Potassium oxide react with nitric acid will produce potassium
nitrate and water.

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mohd faisol mansor/chemistry form 4/chapter 3

i) Iron metal react with chlorine gas will produce iron(III) chloride.

j) Magnesium metal react with nitric acid with produce
magnesium nitrate and hydrogen gas.

k) Zinc metal dissolved in copper(II) chloride will produce zinc
chloride and copper metal.

l) Chlorine gas react with potassium bromide will produce
potassium chloride and bromine gas.

m)Copper(II) carbonate when heated will produce copper(II)
oxide and carbon dioxide.

n) Lead(II) nitrate when heated will produce lead(II) oxide,
nitrogen dioxide gas and oxygen gas.

o) Potassium iodide react with lead(II) nitrate will produce lead(II)
iodide and potassium nitrate solution.

p) Sodium hydroxide react ammonium chloride will produce
sodium chloride, water and ammonia gas.

q) Zinc metal react with hydrochloric acid will produce zinc
chloride and hydrogen gas.

r) Magnesium oxide react with sulphuric acid will produce
magnesium sulphate react with water.

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mohd faisol mansor/chemistry form 4/chapter 3

b) Quantitative Aspect

2H2 (g) + O2 (g) 2H2O(l)

2 molecule 1 molecule 2 molecule
Or Or Or

2 mol 1 mol 2 mol

Note: The coefficient in the reaction tell the exact proportions of
reactant and product in chemical reaction.

Example

1. Copper(II) oxide, CuO reacts with aluminium according to the following
equation.

3CuO (s) + 2Al (s) Al2O3 (s) + 3Cu (s)

Calculate the mass of aluminium required to react completely with 12 g of
copper(II) oxide, CuO. [RAM: O, 16 ; Al, 27 ; Cu, 64]

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mohd faisol mansor/chemistry form 4/chapter 3

2. A student heats 20 g of calcium carbonate, CaCO3 strongly. It decomposes
according to the equation below.

CaCO3 (s) CaO (s) + CO2 (g)

a) If the carbon dioxide produced is collected at room conditions, what is its
volume?

b) Calculate the mass of calcium oxide, CaO produced.

[RAM: C, 12 ; O, 16 ; Ca, 40 ; Molar volume = 24 dm3 mol-1]

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mohd faisol mansor/chemistry form 4/chapter 3

3. Hydrogen peroxide, H2O2 decomposes according to the following equation.

2H2O2 (l) 2H2O (l) + O2 (g)

Calculate the volume of oxygen gas, O2 measured at STP that can obtained
from the decomposition of 34 g of hydrogen peroxide.
[RAM : H, 1 ; O, 16 ; Molar volume = 22.4 dm3 mol-1]

4. 16 g of copper(II) oxide, CuO is reacted with excess methane, CH4. Using the
equation below, find the mass of copper that is produced.

4CuO (s) + CH4 (g) 4Cu (s) + CO2 (g) + 2H2O (l)

[RAM : H, 1 ; C, 12 ; O, 16 ; Cu, 64]

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mohd faisol mansor/chemistry form 4/chapter 4

CHAPTER 4

PERIODIC TABLE OF ELEMENTS

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mohd faisol mansor/chemistry form 4/chapter 4

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mohd faisol mansor/chemistry form 4/chapter 4

Historical Development of Periodic Table

Antoine Lavoiser Johann Dobereiner John Newlands
(1743 – 1794) (1780 – 1849) (1837 – 1898)

first scientist classify divided element arranged element
substances. according their in order of
similar chemical
increasing atomic
properties mass

Lothar Meyer Dmitri Mendeleev
(1830 – 1895) (1834 – 1907)

showing that the arranged the elements in
properties of the elements order of increasing atomic

formed a periodic mass and
pattern against their grouped them
atomic masses. according to similar
chemical properties.

Henry J.G. Moseley Concluded that the
(1887 – 1915) proton number should

Studied the X-ray be the basis for the
spectrum of elements. periodic change of
chemical properties
He rearranged the instead of the atomic
elements in order of
increasing proton number. mass.

Leading to the modern
Periodic Table.

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mohd faisol mansor/chemistry form 4/chapter 4

Arrangement of Element in the Periodic Table

Element in the Element with 18 vertical column
Periodic Table are similar chemical called a group

arranged in an properties are 7 horizontal rows
increasing order of placed in the same called a period

proton number vertical column
ranging 1 to 118.

GROUP GROUP GROUP

The number of Valence electron 1 Valence electron 3
valence electron in and 2 until 8
an atom decides the
position of the group

of an element.

PERIOD Example:

Equal to the number An atom of element X has a proton
of shell occupied number of 15. In which group and period
with electrons in its we can find element X in Periodic Table.
atom

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mohd faisol mansor/chemistry form 4/chapter 4

Exercise Atom, Molecule & Ion

1. Element D has a proton number 19. Where is element D located in Periodic
Table?

2. An atom of element E has 10 neutrons. The nucleon number of element E is 19.
In which group and period of element E located in the Periodic Table?

3. An atom of element G has 3 shell occupied with electrons. It is placed in
Group 17 of the Periodic Table. What is the electron arrangement of atom G?

4. An atom Y is located in Group 18 and period 2 of the periodic Table. What is
the electron arrangement and proton number of atom Y?

5. Element R has a proton number of 11. Its atom has 6 neutrons. In which group
and period can you find element R in the Periodic Table?

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mohd faisol mansor/chemistry form 4/chapter 4

The advantage of grouping elements in the Periodic Table

1. Helps us to study the element systematically especially their
physical and chemical properties.

2. Element with a same number valence electron is place in the
same group because they have the same chemical properties.

3. It could be used to predict undiscovered properties.
4. To relate the characteristic of an element with atomic structure

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mohd faisol mansor/chemistry form 4/chapter 4

GROUP 18 GROUP 18

consist of helium, Known as
neon, argon, NOBLE GAS

krypton, xenon Exist as
and radon monoatomic gas.

Physical Properties of Group 18

COLOUR SOLUBILITY

GROUP 18
NOBLE GAS

ELECTRIC DENSITY
CONDUCTIVITY

MELTING &
BOILING POINT

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mohd faisol mansor/chemistry form 4/chapter 4

The inert properties of G18

All noble gas are inert which means unreactive.
Noble gas are inert because the outermost occupied shell are full.

This electron arrangements are very stable.
Helium have 2 valence electron, this electron arrangement is called
duplet electron arrangement whereas other noble gas have eight

valence electron which called octet electron arrangement.

p/s: All other element try to achieve noble gas electron arrangement to
become stable.

The Physical Properties of G18

The physical properties vary down the group.
physical properties vary down the group are related to atomic size.

Melting and boiling point of an element increase when going
down the group because the atomic sizes increase, the forces
attraction (Van der Waals forces) becomes stronger. Thus more

heat energy is required to overcome the forces.
The strength of Van der Waals forces propotional to the size of

particle

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mohd faisol mansor/chemistry form 4/chapter 4

Uses of Noble Gas Elements

[ State the element of group 18 ]

Fill light bulb laser for repair retina,
photographic flash lamps

treatment cancer fill airships and weather
balloons

Car bulb, use in bubble chamber

advertising light and 62
television tubes

mohd faisol mansor/chemistry form 4/chapter 4

Exercise

1. Table below shows the electron arrangements of atoms of elements P, Q,
and R.

Element Electron Arrangement
P 2.8
Q
R 2.8.18.8
2.8.18.32.18.8

a) Arrange the element in ascending order of boiling points. Give reasons for
your answer.

b) Elements P, Q, and R are chemically unreactive. Why?

2) What is the meaning of
a) Duplet electron arrangement
b) Octet electron arrangement

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mohd faisol mansor/chemistry form 4/chapter 4

GROUP 1 Consist of elements
such as lithium,
Known as Alkali
Metals. sodium, potassium,
rubidium, caesium
Have valence
electron of 1. and francium.

Physical Properties of Group 1

HARDNESS GROUP 1 APPEARANCE
ALKALI METALS DENSITY
ELECTRIC
CONDUCTIVITY

MELTING
POINT

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mohd faisol mansor/chemistry form 4/chapter 4

Element Atomic Size Melting / Density Hardness
Boiling
point

Lithium
Sodium
Potassium
Rubidium
Caesium
Francium

A melting point of a metal indicates the strength of its metallic bonding in its
structure.

Generally, the strength of metallic bonding is directly proportional to the number
of valence electron per atom divided by the radius of a metal.

A metallic bond can be defined as the electrostatic force between the
positively charged metallic ions and the ‘sea’ of electrons.

Electropositivity is the measurement of an atom to release an electron and form
positive ion

When going down the group, what happen to the electropositivity of the
element? Why?

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mohd faisol mansor/chemistry form 4/chapter 4

Chemical Properties of Group 1 Elements

React vigorously with water to produce alkaline metal hydroxide solution
and hydrogen gas, H2.

2Li (s) + 2H2O 2LiOH (aq) + H2 (g)

Burn in oxygen gas rapidly to produce solid metal oxide

4Li (s) + O2 (g) 2 Li2O (s)

Solid metal oxide dissolve in water to form alkaline metal hydroxide

Li2O (s) + H2O 2LiOH (aq)

Alkaline metal burn in chlorine gas, Cl2 to form white solid metal chloride

2Na (s) + Cl2 2NaCl (aq)

Exercise :
1. Why does Group 1 element have similar chemical properties?

2. Why is paraffin oil used to store metals such as sodium and potassium?

3. Element in Group 1 has similar chemical properties but differ in reactivity.
Why?

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mohd faisol mansor/chemistry form 4/chapter 4

To investigate the chemical properties of Lithium, Sodium & Potassium

1) The reaction of alkali metals with water 2) The reaction of alkali metals with O2 gas

[ Draw the diagram ] [ Draw the diagram ]

[ Discussion ]

1. Why are the experiments involving sodium and potassium demonstrated by
your teacher and not carried out by the students?

2. Write the chemical equations for the reactions of lithium, sodium and
potassium with

a) Water, H2O

Lithium :

Sodium :

Potassium :

b) Oxygen gas, O2

Lithium :

Sodium :

Potassium :

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mohd faisol mansor/chemistry form 4/chapter 4

3. Write the chemical equations for the reactions between the products from

the combustion of each alkali metal with water.

Lithium :

Sodium :

Potassium :

Exercise

1. A student performs two experiments to study the reaction of alkali metal with
water.

Experiment Metal used Observation
1 Sodium
2 Lithium Sodium moves rapidly and randomly on the
water surface and emits ‘hiss’ sounds.

Lithium moves slowly on the water surface.

a) Write the chemical equation for the reaction between sodium and lithium

with water.

Lithium :

Sodium :

b) Between reactions of Experiment 1 and 2, which is more vigorous? Explain
your answer from the point of electron arrangement.

c) Explain why sodium and lithium show similar chemical properties?

d) Calculate the volume of hydrogen gas produced if 2.3 g of sodium is used.
[RAM: Na, 23 ; molar volume: 24 dm3 mol-1]

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mohd faisol mansor/chemistry form 4/chapter 4

GROUP 17 GROUP 17 GROUP 17

consist of fluorine, Known as Elements are
chlorine, bromine, HALOGENS. poisonous.

iodine and Have valence Exist as diatomic
astatine. electron of 7. molecules.

Element Symbol of Symbol of Physical Colour
Atom Molecule state at
Fluorine
Chlorine room
Bromine condition

Iodine
Astatine

Melting & Boiling Physical State Electric
Point HALOGENS Conductivity

Density Smell

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mohd faisol mansor/chemistry form 4/chapter 4

Element Atomic Melting / Density Electronegativity
Size Boiling
point

Fluorine
Chlorine
Bromine

Iodine
Astatine

Electronegativity is an ability of atom to receive an electron to become
negative charged ions.

All halogen have seven valence electron. Their atoms always gain one electron
to form an ion with a charge of –1, in order to achieve stable octet electron
arrangement.

Chemical Properties of Group 17 Elements

Halogen react with water to produce two acids

Cl2 + H2O HCl + HOCl

Halogen react with metal to produce metal halides

2Fe (s) + 3Cl2 (g) FeCl3 (s)

Halogen react with sodium hydroxide solution to form sodium
halide and sodium halate (I) and water

I2(s) + 2NaOH (aq) NaI (aq) + NaOI (aq) + H2O (l)

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mohd faisol mansor/chemistry form 4/chapter 4

To Investigate the Chemical Properties of Halogens

[Draw the Apparatus]

SECTION A : Reaction with Water

1) Chlorine 2) Bromine 3) Iodine

SECTION B : Reaction with Iron

1) Chlorine 2) Bromine 3) Iodine

SECTION C : Reaction with Sodium Hydroxide

1) Chlorine 2) Bromine 3) Iodine

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mohd faisol mansor/chemistry form 4/chapter 4

[Discussion]

1. Name the products formed when chlorine, bromine, and iodine
react with water.

Chlorine :
Bromine :
Iodine :

2. Write the chemical equations for the reaction of chlorine,
bromine and iodine with water.

Chlorine :
Bromine :
Iodine :

3. What is the function of soda lime in SECTION B?

4. Name the products formed when chlorine, bromine, and iodine
react with iron.

Chlorine :
Bromine :
Iodine :

5. Write the chemical equation for the reaction of chlorine,
bromine, and iodine with iron.

Chlorine :
Bromine :
Iodine :

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mohd faisol mansor/chemistry form 4/chapter 4

4. Name the products formed when chlorine, bromine, and iodine
react with sodium hydroxide solution.

Chlorine :
Bromine :
Iodine :

5. Write the chemical equation for the reaction of chlorine,
bromine, and iodine with sodium hydroxide solution.

Chlorine :
Bromine :
Iodine :

6. Describe the changes in reactivity of Group 17 elements when
going down the group. Explain your answer.

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mohd faisol mansor/chemistry form 4/chapter 4

Exercise

1. Table below shows several halogen elements with their proton numbers.

Halogen Proton Number
X 9
Y 17
Z 35

a) State the group that the halogen elements belong to in the Periodic Table.

b) i) Write the electron arrangement of elements X and Y.

ii) From your answers in (b)(i), deduce the period of elements X and Y.

c) Draw the electron arrangement of element Y.

d) State the changes of properties of halogens down the group from X to Z in
terms of:

i) Atomic radius

ii) Electronegativity

iii) Melting point and boiling point

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mohd faisol mansor/chemistry form 4/chapter 4

e) i) Iron glow brightly when reacting with element Y. Write the chemical
reaction to represent this reaction.

ii) Predict the observation for the reaction between iron and element Z.
iii) Between Y and Z, which is more reactive? Explain why.

f) i) Determine the elements X, Y and Z.
ii) State the colour for each elements X, Y, and Z.
iii) Why the physical state of halogen differ when down the group?

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mohd faisol mansor/chemistry form 4/chapter 4

Comparison & Similarities between Group 1 and Group 17

Properties Group Down the Group
1
Atomic 17
Size 1
17
Melting & 1
Boiling 17
Point 1
17
Density

Reactivity

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mohd faisol mansor/chemistry form 4/chapter 4

Elements in a Period 3

Element Sodium Magnesium Aluminium Silicon Phosphorus Sulphur Chlorine Argon

Symbol

Proton Number

Electron
Arrangement

Metal Properties

Physical State
[RC]

Atomic Radius

Electronegativity

Property of the
oxide

The proton number ____________ by one unit.
All atom of the element have __________ shells occupied by electron.

The number of valence electron ____________ from 1 to 8.
All element exist as __________ except chlorine and argon.

The atomic radius of element ________________.

The electronegativity of element ______________.
The oxides of element in Period 3 change from basic to acidic properties,
therefore the metallic properties decrease across the period. On the other

hand non-metallic properties of the elements increase.

Note: the atomic radius ______________ and electro negativity ______________
due to the increasing nuclei attraction on the valence electrons.
(nuclei attraction force increase with the increase of proton number)

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mohd faisol mansor/chemistry form 4/chapter 4

Transition Elements

Transition elements are elements from Group 3 to Group 12

All the elements are metals, usually solids with shiny surfaces, ductile,
malleable and have tensile strength.

Have high melting and boiling point as well as high density.
Good conductors of heat and electricity.

Three special characteristics of transition element
 Show different oxidation number in their compound.

 Form coloured ions or compound.

 Act as catalysts.

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mohd faisol mansor/chemistry form 4/chapter 5

CHAPTER 5

CHEMICAL BONDS

Almost all chemical Atom of other Less stable atom
substances exist as element that have will tend to release,
compounds in nature
except inert gases less than eight accept or share
valence electron electron to
and other stable
element (such as are not stable achieve the stable
gold and silver). electron

All other elements arrangement
combine together to
achieve the stability by of an inert gas.
forming duplet or octet
electron arrangement by Two types of chemical
bonds formed:-
i) The transfer of electron
i) ionic bonds
ii) Sharing of electron ii) covalent bond

Ionic Bond

Covalent Bond

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mohd faisol mansor/chemistry form 4/chapter 5

Ionic Bond

Ionic bond formed Formation of Formation of
when metal atom Cation Anion
transfer electrons to
non-metal atom to

form ionic
compound.

Metal atom from Non-Metal atom
from group 15, 16
group 1,2 and 13
and 17 tend to
tend to released all accept the
electrons.
Example: their valence
electrons.

Draw the formation

of sodium ion.

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mohd faisol mansor/chemistry form 4/chapter 5

Exercise

1. Draw the formation of the following cations:
a) Potassium ion

b) Magnesium ion

c) Aluminium ion

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mohd faisol mansor/chemistry form 4/chapter 5

2. Draw the formation of the following anions:
a) Chloride ion

b) Oxide ion

c) Nitride ion

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mohd faisol mansor/chemistry form 4/chapter 5

Formation of Ionic Compound

1. Metal atom and non-metal atom are not stables.

2. To achieve stability, metal atom will combine with non- metal atom by transfer of

electrons.

3. Metal atoms will donate electrons to form cation.

X X+ + e

4. Non-metal atom will accept electrons to form anion.
Y-
Y+e

5. Both ions already achieve stable duplet/octet electron arrangement.

6. The formation of cation & anion will create strong electrostatic force between the ions.

7. Ionic bond will pull cation & anion together in crystal lattice form.

8. The compound formed called as ionic compound.

Example: Formation of Sodium Chloride, NaCl

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mohd faisol mansor/chemistry form 4/chapter 5

Exercise

1. Explain the formation of ionic compound below:
a) Lithium fluoride

b) Magnesium oxide

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mohd faisol mansor/chemistry form 4/chapter 5

c) Calcium chloride

d) Aluminium oxide

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mohd faisol mansor/chemistry form 4/chapter 5

2. Draw the formation of the following ionic compound:
a) Lithium fluoride

b) Magnesium oxide

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mohd faisol mansor/chemistry form 4/chapter 5

c) Calcium chloride

d) Aluminium oxide

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mohd faisol mansor/chemistry form 4/chapter 5

Ionic Equations
Equation that represent the formation of ionic compounds are
known as ionic equation.
Example:
a) Formation of sodium chloride, NaCl

i) Chemical Equation :
ii) Half-ionic Equation :

b) Formation of Magnesium oxide, MgO
i) Chemical Equation :
ii) Half-ionic Equation :

Exercise

1. Write an ionic equation of the following compound
a) Lithium fluoride

b) Magnesium chloride

c) Aluminium oxide

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mohd faisol mansor/chemistry form 4/chapter 5

Exercise

1. Atom X and Y each have proton numbers of 3 and 8. What is
the ionic compound formula formed between atoms X and Y?

2. Complete each of the following table:

Atom Proton Electron Ionic Atom Proton Electron Ionic Compound
Number Arrangement Formula Number Arrangement Formula Formula

A3 B9

1 C 11 D8

2E 12 F 17

3 G 20 H9

4I 19 J 17

5K 13 L8

6 M 13 N 17

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mohd faisol mansor/chemistry form 4/chapter 5

Covalent Bond

Covalent bond is the Three types of covalent
chemical bond bonds:

formed through the single covalent bond
sharing of electron ( sharing one pair of e )
between two or more double covalent bond
non metal atom to ( sharing two pairs of e )

form covalent triple covalent bond
compound. ( sharing three pairs of e )

Single Covalent Bond
Example:

Draw the formation of chlorine gas.

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Double Covalent Bond
Example:

Draw the formation of oxygen gas.

Triple Covalent Bond
Example:

Draw the formation of nitrogen gas.

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mohd faisol mansor/chemistry form 4/chapter 5

Exercise

1. Draw the formation of the following compound.
a) water

b) Carbon dioxide

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mohd faisol mansor/chemistry form 4/chapter 5

c) Ammonia

b) Tetrachloromethane , CCl4.

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mohd faisol mansor/chemistry form 4/chapter 5

Determine the Formula of Covalent Compound
Guideline:

1. State the electron configuration of atoms.
- Make sure electron valence for both atoms is either 4, 5, 6, and 7.

2. Determine the number of electrons needed to achieve stability.
3. Write the number of electron needed to achieve stability at the

below right corner of each atom.
4. Cross the number.

Example:
If atom P has 8 protons and atom Q has 9 protons, determine the

formula of the covalent compound formed.

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mohd faisol mansor/chemistry form 4/chapter 5

Exercise

1. Atoms K and S each have a proton number of 6 and 8
respectively. What is the formula of the covalent compound
which is formed by K and S?

2. Complete the table below to show the formulae of compounds
which are formed.

Proton Electron Proton Electron Compound
Atom config. Atom config. formula

number number

A6 2.4 B 9 2.7 AB4

C6 D 16
E7 F1

G1 H8

I6 J 17

K6 L8

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mohd faisol mansor/chemistry form 4/chapter 5

Comparison between the formation of the ionic bond and the
covalent bond

IONIC BOND COVALENT BOND

Similarity

Differences
Formation

Particles

Force of
Attraction

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mohd faisol mansor/chemistry form 4/chapter 5

The following figure compares and contrasts the properties
of ionic compound and covalent compound

IONIC COMPOUND COVALENT COMPOUND
PROPERTIES

Melting &
Boiling point

Electric
Conductivity

Physical State

Solubility

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mohd faisol mansor/chemistry form 4/chapter 5

Exercise

1. (a)Table 1.1 shows the proton number of three elements, X, Y, and
Z. The letters used do not represent the actual symbols of the
elements.

Element Proton Number
X 6
Y 12
Z 17

Table 1.1

i) Write the electron arrangement of:

Atom Y : _______________________________________________

The ion of Z : ___________________________________________

ii) Write the formula of the compound formed between
elements Y and Z.

________________________________________________________

iii) Element X reacts with element Z to form a covalent
compound with a formula XZ4. State two physical
properties of this compound.

________________________________________________________

________________________________________________________

i) Draw the electronic structure of the compound XZ4.

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