About this book
O LEVEL TOPICAL CHEMISTRY provides a thorough revision for students taking the GCE
O-Level Chemistry Examination.
This book contains:
• Past Examination Questions
Questions from past examinations provide the best practice. They also provide insight
into the type and style of questions often asked in an examination.
• Latest Examination Papers
The latest examination papers are included for timed practice, providing students
with an idea of what is expected of them in the actual examination.
• Comprehensive Answers (Separate booklet)
Thought process
This feature provides guidance to each question so as to assist students through their
thought processes for effective learning and revision.
Answers with explanatory notes for Paper 1, and comprehensive answers to Paper 2 are
provided for reference and self-study purposes.
The Editorial Team
1 Pre&Cont_OL T Chemistry.indd 1
9/12/2016 1:24:22 PM
CONTENTS
THE PERIODIC TABLE OF THE ELEMENTS
SECTION I
Topic 1.1
Topic 1.2
Topic 1.3
EXPERIMENTAL CHEMISTRY
Experimental Design.................................................................................... (1.1)1 - 2
Methods Of Purification And Analysis........................................................ (1.2)1 - 8
Identification Of Ions And Gases................................................................. (1.3)1 - 4
SECTION II
Topic 2.1
Topic 2.2
Topic 2.3
Topic 3
ATOMIC STRUCTURE AND STOICHIOMETRY:
THE PARTICULATE NATURE OF MATTER
Kinetic Particle Theory................................................................................ (2.1)1 - 6
Atomic Structure.......................................................................................... (2.2)1 - 4
Structure And Properties Of Materials
Bonding: Ionic, Covalent & Metallic........................................................... (2.3)1 - 14
Formulae, Stoichiometry And The Mole Concept....................................... (3)1 - 8
SECTION III
Topic 4
Topic 5
Topic 6.1
Topic 6.2
Topic 7.1
Topic 7.2
Topic 7.3
CHEMISTRY OF REACTIONS
Electrolysis................................................................................................... (4)1 - 16
Energy From Chemicals.............................................................................. (5)1 - 12
Chemical Reactions: Speed Of Reaction..................................................... (6.1)1 - 10
Chemical Reactions: Redox......................................................................... (6.2)1 - 6
Acids And Bases.......................................................................................... (7.1)1 - 12
Salts.............................................................................................................. (7.2)1 - 4
Ammonia...................................................................................................... (7.3)1 - 6
SECTION IV
Topic 8
Topic 9.1
Topic 9.2
PERIODICITY
The Periodic Table....................................................................................... (8)1 - 14
Metals: Properties Of Metals
Reactivity Series.......................................................................................... (9.1)1 - 12
Metals: Extraction Of Metals
Recycling Of Metals
Iron............................................................................................................... (9.2)1 - 10
SECTION V ATMOSPHERE
Topic 10
Air................................................................................................................ (10)1 - 10
SECTION VI
Topic 11.1
Topic 11.2
ORGANIC CHEMISTRY
Fuels And Crude Oil
Alkanes, Alkenes, Alcohols And Carboxylic Acids.................................... (11.1)1 - 28
Macromolecules........................................................................................... (11.2)1 - 12
O LEVEL CHEMISTRY EXAMINATION YEAR 2016 PAPERS 1 AND 2 ............... (2016)1 - 36
ANSWERS (separate booklet) Topics 1.1 - 11.2
Latest Examination Papers
1 Pre&Cont_OL T Chemistry.indd 2
9/12/2016 1:24:22 PM
1 Pre&Cont_OL T Chemistry.indd 3
9/12/2016 1:24:22 PM
SECTION I
EXPERIMENTAL CHEMISTRY
TOPIC 1·1 EXPERIMENTAL DESIGN
PAPER 1
Each question below is provided with four answers. Select the correct answer and write A, B, C or D
in the brackets provided.
1. The diagram shows apparatus used to obtain carbon monoxide.
What is the main purpose of Y? A to dry the gas
B to remove hydrogen chloride from the gas
C to remove carbon dioxide from the gas
D to prevent water being sucked back on to the hot carbon
(2007 P1 Q2)
( )
2. The diagram shows the apparatus used to prepare a liquid compound L.
Compound L (boiling point 57 ºC) is made by heating together two liquids, M (boiling point 78 ºC) and
N (boiling point 95 ºC). The reaction is slow.
What is the purpose of the condenser?
(2008 P1 Q1)
A to allow liquid L to escape as fast as it is formed
B to enable M and N to mix more efficiently
C to keep air away from the reacting liquids
D to prevent M and N from escaping before the reaction is complete
( )
(1·1)
OL Topical Chemistry 2017.indb 1
12/9/2016 10:40:10 AM
3. Magnesium ribbon was reacted with excess dilute hydrochloric acid.
The graph shows the volume of hydrogen gas evolved at 20 second intervals until the reaction had
finished.
Which piece of apparatus would be suitable for measuring the volume of hydrogen gas evolved?
(2015 P1 Q1)
A
B
C
D
( )
(1·1)
OL Topical Chemistry 2017.indb 2
12/9/2016 10:40:11 AM
TOPIC 1·2 METHODS OF
PURIFICATION AND ANALYSIS
PAPER 1
Each question below is provided with four answers. Select the correct answer and write A, B, C or D
in the brackets provided.
1. What is necessary for two substances to be separated by paper chromatography? A
B
C
D
They are both liquids.
They are both soluble in the same solvent.
They have different densities.
They have different colours. (2007 P1 Q1)
( )
2. Which mixture can be separated into its components by adding water, stirring and filtering?
(2008 P1 Q8)
A
B
C
D
calcium carbonate and sodium chloride
magnesium and iron
sodium chloride and copper(II) sulphate
sulphuric acid and hydrochloric acid
( )
3. Which substance could not sublime when heated from room temperature in the laboratory?
(2008 P1 Q9)
A
B
C
D
solid carbon dioxide
ammonium chloride
iodine
mercury
( )
4. Which process takes place when crystals of sugar are placed in a beaker of water at constant
temperature?
(2009 P1 Q1)
A
B
C
D
diffusion
evaporation
melting
precipitation
( )
(1·2)
OL Topical Chemistry 2017.indb 1
12/9/2016 10:40:11 AM
5. The white solid ammonium chloride sublimes on heating.
Which method could be used to separate a mixture of solid sodium chloride, NaCl, and solid ammonium
chloride, NH4Cl?
(2009 P1 Q3)
A
C
D
B
( )
6. The table shows the colours and the solubilities in water of four solids.
solid
W
X
Y
Z
colour
blue
blue
white
white
solubility in water
insoluble
soluble
insoluble
soluble
A mixture containing two of the solids is added to excess water, stirred and filtered.
A blue filtrate and a white residue are obtained.
Which two solids are present in the mixture?
A W and X
B W and Y
(2009 P1 Q5)
C X and Y
D X and Z
( )
(1·2)
OL Topical Chemistry 2017.indb 2
12/9/2016 10:40:12 AM
7. An aqueous solution of calcium chloride is distilled.
What is the temperature shown by the thermometer and what is left in the distillation flask?
(2009 P1 Q33)
thermometer
final contents of
reading / ºC
distillation flask
A
97
no residue
B
100
white residue
C
103
no residue
106
residue
D
white
( )
8.
A student accidentally mixed 50 cm3 of water with 50 cm3 of oil.
Which method would allow him to obtain 25 cm3 of the oil most easily?
A chromatography
C filtration
B evaporation
D use of a separating funnel
(2012 P1 Q2)
( )
9. A series of experiments was carried out in order to determine how the rate of reaction of magnesium with
hydrochloric acid varied with the concentration of the acid. In each experiment, excess magnesium was
reacted with 50 cm3 of hydrochloric acid in a conical flask.
Five other pieces of apparatus were available.
Which four pieces of apparatus would be needed to carry out the experiment?
A 1, 2, 3 and 4
C 1, 3, 4 and 5
B 1, 2, 3 and 5
D 2, 3, 4 and 5
(2013 P1 Q1)
( )
(1·2)
OL Topical Chemistry 2017.indb 3
12/9/2016 10:40:13 AM
10. The apparatus shown is used to distil ethanol (boiling point 78°C) from a mixture of ethanol and
water.
Which graph shows the change in concentration of the ethanol in flask F as the distillation proceeds? (2013 P1 Q4)
A
C
B
D
( )
(1·2)
OL Topical Chemistry 2017.indb 4
12/9/2016 10:40:13 AM
11. A paper chromatogram was prepared using a mixture of substances. After drying, the chromatogram is
shown in the diagram.
Which statement is correct?
A
B
C
D
(2014 P1 Q1)
Locating agents are always needed to interpret a chromatogram.
The chromatography paper must have been placed with the solvent below level Z.
There must have been two substances present in the mixture.
The substance at level X has a lower Rf value than the substance at level Y.
( )
12. Three separations are listed.
1 obtaining water from sodium chloride solution
2 obtaining iodine from a mixture of iodine and nickel
3 obtaining solid sodium chloride from aqueous sodium chloride
Which techniques would be involved in these separations?
(2014 P1 Q2)
1
2
3
A
distillation
sublimation
evaporation
B
distillation
sublimation
filtration
C
filtration
crystallisation
evaporation
D
sublimation
crystallisation
filtration
13. Which physical processes could be used to separate diesel and water?
A
B
C
D
1
2
3
4
( )
(2015 P1 Q2)
distillation
filtration
sublimation
use of a separating funnel
1, 2, 3 and 4
1, 2 and 3 only
1 and 2 only
1 and 4 only
( )
(1·2)
OL Topical Chemistry 2017.indb 5
12/9/2016 10:40:14 AM
PAPER 2
SECTION A
Answer the following questions in the spaces provided.
1. Aspirin is a medicine that is used as a painkiller. It is made from salicylic acid.
(a) A student makes a sample of aspirin. He thinks it contains some impurities.
(i) The student tests the melting point of his sample of aspirin.
(ii) The student uses chromatography to produce a chromatogram.
He uses his own aspirin and pure samples of aspirin and salicylic acid.
The diagram shows his chromatogram.
What information does the chromatogram give about the purity of the student’s aspirin?
(b) Aspirin is a weak acid.
Explain how he can use the result of the test to find out whether his sample contains
impurities.
[2]
[2]
Explain what is meant by the term weak acid.
[1]
(1·2)
OL Topical Chemistry 2017.indb 6
12/9/2016 10:40:14 AM
(c) The student buys and tests some tablets that contain aspirin.
He performs a titration using a crushed tablet and aqueous sodium hydroxide.
The formula for aspirin can be represented as
– COOH. The equation for the reaction between
aspirin and aqueous sodium hydroxide is shown below.
– COOH + NaOH →
– COONa + H2O
The table shows the results of the student’s titration.
concentration of aqueous sodium hydroxide used
0.10 mol/dm3
volume of aqueous sodium hydroxide needed for neutralisation
16.70 cm3
relative molecular mass of aspirin
180
The label on the bottle of tablets states that each tablet contains 300 mg of aspirin. (1000 mg = 1 g)
Do the student’s results agree with this value?
Show your working.
[3]
(d) Some tablets that contain aspirin also contain citric acid.
The student does another titration using one of these tablets.
Explain why the mass of aspirin he calculates from his titration results is incorrect.
[2]
(2013 P2A Q6)
(1·2)
OL Topical Chemistry 2017.indb 7
12/9/2016 10:40:14 AM
SECTION B
Answer the following questions.
1. Ephedrine and insulin are both drugs that are banned for use by athletes.
One way that athletes can be tested for the banned drugs is by chromatography of urine samples.
The diagram shows a chromatogram for ephedrine and insulin and the urine samples from four
athletes.
(a) What does the chromatogram show about the drugs used by each of the four athletes?
[2]
(b) A similar test was carried out on the urine of a fifth athlete.
This diagram shows the chromatogram for the fifth athlete.
Show, by using Rf values, which one of the banned drugs this athlete has used.
(c) The chromatograms are run using methanol as a solvent. A locating agent is used.
(i) Describe, with the help of a diagram, how to set up and carry out the chromatography.
(ii) Explain why a locating agent needs to be used.
[3]
[4]
[1]
(2007 P2B Q10 OR)
(1·2)
OL Topical Chemistry 2017.indb 8
12/9/2016 10:40:14 AM