Cambridge IGCSE™

CHEMISTRY 0620/22
Paper 2 Multiple Choice (Extended) October/November 2023
45 minutes

You must answer on the multiple choice answer sheet.

*3509125559*

You will need: Multiple choice answer sheet

Soft clean eraser
Soft pencil (type B or HB is recommended)

INSTRUCTIONS
 There are forty questions on this paper. Answer all questions.
 For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
 Follow the instructions on the multiple choice answer sheet.
 Write in soft pencil.
 Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
 Do not use correction fluid.
 Do not write on any bar codes.
 You may use a calculator.

INFORMATION
 The total mark for this paper is 40.
 Each correct answer will score one mark.
 Any rough working should be done on this question paper.
 The Periodic Table is printed in the question paper.

This document has 16 pages.

IB23 11_0620_22/4RP
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1 Part of a cooling curve for water is shown.

100

temperature / qC
X Y
0

time / min

What is occurring between points X and Y?

A Steam is condensing into water.

B The temperature of the water is decreasing.
C Ice is melting.
D Particles are losing heat to the surroundings.

2 Which statements about clean, dry air are correct?

1 It is a mixture of elements only.

2 It is a mixture of elements and compounds.
3 It contains only non-metals.

A 1 and 3 B 1 only C 2 and 3 D 2 only

3 A representation of an atom is shown.

+ +
– – + + + – –
+

What is the nucleon number of this atom?

A 6 B 7 C 12 D 13

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4 The percentage abundances of three isotopes in a sample of neon are shown.

percentage
isotope
abundance / %
20
10 Ne 90.48
21
10 Ne 0.27
22
10 Ne 9.25

What is the relative atomic mass, Ar, of this sample of neon?

A 10.19 B 20.19 C 21.00 D 30.19

5 Potassium reacts with iodine to form potassium iodide.

Which statement about potassium iodide is correct?

A Each potassium atom shares a pair of electrons with an iodine atom.

B In potassium iodide, the particles of potassium have more protons than electrons.
C Potassium iodide has a high melting point because it is a covalent compound.
D Potassium iodide has a low melting point because it is an ionic compound.

6 Which substance has the lowest melting point?

A graphite
B methanol

C silicon(IV) oxide

D sodium chloride

7 The diagram shows the structure of a molecule of ethyl ethanoate.

H O
H C C H H

H O C C H

H H

What is the molecular formula of a molecule of ethyl ethanoate?

A CHO B C4H8O2 C C4(H2)2(O2) D C2H4O

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8 A hydrocarbon contains 85.7% of carbon by mass.

What is the empirical formula of the hydrocarbon?

A CH2 B CH4 C C2H5 D C3H6

9 The formula of a compound containing element X is Na2X2O3.

The relative formula mass of the compound is 158.

What is the relative atomic mass of X?

A 32 B 59.5 C 64 D 119

10 Dilute aqueous potassium chloride is electrolysed using platinum electrodes.

Which row identifies the product at each electrode?

anode cathode

A chlorine hydrogen
B chlorine potassium
C oxygen hydrogen
D oxygen potassium

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11 Concentrated aqueous copper(II) chloride is electrolysed using copper electrodes, as shown.

power supply

+ –
copper electrodes

aqueous copper(II) chloride

What happens to the mass of each electrode during this process?

positive electrode negative electrode

A decreases decreases
B decreases increases
C increases decreases
D increases increases

12 The initial and final temperatures of four different reactions are measured.

Which reaction is the least exothermic?

initial final
temperature temperature
/ C / C

A 19 25
B 21 18
C 22 17
D 22 26

13 Which equation represents an endothermic reaction?

A Cl 2(g)  2Cl (g)

B CH4(g) + 2O2(g)  CO2(g) + 2H2O(l)

C H(g) + H(g)  H2(g)

D 2K(s) + 2H2O(l)  2KOH(aq) + H2(g)

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14 Methane burns in oxygen to form carbon dioxide and water.

CH4(g) + 2O2(g)  CO2(g) + 2H2O(l)

The bond energies are shown.

bond energy
bond
in kJ / mol

C–H 410
C–O 360
C=O 805
O–H 460
O–O 146
O=O 496

What is the energy change for this reaction?

A –818 kJ / mol B –102 kJ / mol C +102 kJ / mol D +818 kJ / mol

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15 Hydrochloric acid is added to excess calcium carbonate in two separate experiments.

Two different concentrations of hydrochloric acid are used but the temperature is the same in
both experiments.

The graph of the results shows the volume of carbon dioxide gas given off over time.

2.0 mol / dm3

volume of
carbon dioxide
given off

1.0 mol / dm3

time

Which row is correct?

particles in 2.0 mol / dm3

compared to 1.0 mol / dm3
collision rate collision energy

A higher no change
B higher higher
C lower no change
D lower higher

16 The decomposition of dinitrogen tetroxide, N2O4, into nitrogen dioxide, NO2, is a reversible
reaction.

The equation for the reaction is shown.

N2O4(g) 2NO2(g)

The forward reaction is endothermic.

Which row shows the effect on the position of equilibrium and the rate of the reverse reaction
when the temperature is increased?

position of rate of the

equilibrium reverse reaction

A shifts to the left decreases

B shifts to the left increases
C shifts to the right decreases
D shifts to the right increases

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17 In a blast furnace, iron(III) oxide is converted to iron and carbon monoxide is converted to
carbon dioxide.

Fe2O3 + 3CO  2Fe + 3CO2

What happens to each of these reactants?

A Both iron(III) oxide and carbon monoxide are oxidised.

B Both iron(III) oxide and carbon monoxide are reduced.

C Iron(III) oxide is oxidised and carbon monoxide is reduced.

D Iron(III) oxide is reduced and carbon monoxide is oxidised.

18 Which row describes what happens to Fe2+ ions when they are oxidised?

oxidation number
electron movement
of iron

A they gain electrons decreases

B they gain electrons increases
C they lose electrons decreases
D they lose electrons increases

19 In which reaction does an acid react with a base?

A Dilute sulfuric acid is added to a piece of magnesium ribbon producing hydrogen.

B Dilute sulfuric acid is added to aqueous barium chloride producing a white precipitate of
barium sulfate.

C Aqueous sodium hydroxide is added to aqueous copper(II) sulfate producing a blue

precipitate of copper(II) hydroxide.

D Aqueous sodium hydroxide is added to solid ammonium sulfate producing gaseous

ammonia.

20 Which element forms an oxide that reacts with an aqueous solution of a base?

A argon
B sulfur
C magnesium
D copper

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21 Which method is used to produce insoluble salts?

A addition of excess insoluble base to an acid

B addition of excess metal to an acid
C precipitation using two aqueous solutions
D titration using an acid and an alkali

22 The noble gases are in Group VIII of the Periodic Table.

Some properties of the first four noble gases are shown.

boiling point density

noble gas
in C in g / dm3

helium –267 0.179

neon –246 0.900
argon –186 1.782
krypton –152 3.708

Which row identifies the trends in boiling point and in density as Group VIII is descended?

boiling point density

A decreasing increasing
B increasing increasing
C decreasing decreasing
D increasing decreasing

23 Some properties of element R are shown.

melting point in C 98
boiling point in C 883
reaction with cold water gives off H2 gas
reaction when heated with oxygen burns to give a white solid

In which part of the Periodic Table is R found?

A Group I
B Group VII
C Group VIII
D transition elements

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24 Which pair of compounds shows that transition elements have variable oxidation states?

A Cr2O3 and CrBr3

B CuSO4 and CuCl 2
C Fe2O3 and FeCl 2

D NiO and NiCl 2

25 The list gives the order of some metals and hydrogen in the reactivity series.

Metal X is also included.

most reactive K
Mg
Zn
H
X
least reactive Cu

Which row shows the properties of metal X?

reacts with oxide reduced

dilute acids by carbon

A no no
B no yes
C yes no
D yes yes

26 When zinc is added to an aqueous solution containing magnesium ions, there is no reaction.

Which species has the greatest tendency to lose electrons?

A Mg B Mg2+ C Zn D Zn2+

27 Which gas in the air is needed for iron to rust?

A argon
B carbon dioxide
C nitrogen
D oxygen

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28 Which coating prevents iron from rusting even when the coating is damaged?

A grease
B paint
C plastic
D zinc

29 Why is limestone added to the blast furnace?

A It neutralises the molten slag produced.

B It reacts with impurities to form slag.

C It releases carbon dioxide which reduces the iron(III) oxide.

D It removes acidic gases such as carbon dioxide.

30 The flow chart shows stages in the treatment of river water to produce drinking water.

river sedimentation stage stage drinking

water tank J K water

What occurs at stages J and K?

J K

A distillation chlorination
B distillation filtration
C filtration chlorination
D filtration distillation

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31 Carbon dioxide acts as a greenhouse gas by interacting with a particular type of energy that
radiates from the Earth’s surface into the atmosphere.

Which type of energy is involved and what happens when this energy interacts with
carbon dioxide molecules?

type of
what happens
energy involved
A thermal carbon dioxide molecules increase
the Earth’s energy loss to space
B thermal carbon dioxide molecules
absorb the energy
C light carbon dioxide molecules increase
the Earth’s energy loss to space
D light carbon dioxide molecules
absorb the energy

32 Oxides of nitrogen, such as NO and NO2, are formed in the petrol engines of cars.

They are removed from the exhaust gases by reactions in the car’s catalytic converter.

Which row describes how oxides of nitrogen are formed in a petrol engine and a reaction that
happens in the catalytic converter?

a reaction that happens

how oxides of nitrogen are formed
in the catalytic converter

A by the reaction between 2NO + 2CO  N2 + 2CO2

nitrogen and oxygen from the air
B by the reaction between 2NO + 2H2  N2 + 2H2O
nitrogen and oxygen from the air
C by the reaction between nitrogen 2NO + 2CO  N2 + 2CO2
compounds in petrol and oxygen from the air
D by the reaction between nitrogen 2NO + 2H2  N2 + 2H2O
compounds in petrol and oxygen from the air

33 Which diagram shows the displayed formula for the named organic compound?

A B C D

H O H H H O H H H

H C C O O H H C C H H C C H H C C H

H H H H H H H
ethanoic acid ethene ethanol methane

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34 What is the total number of covalent bonds in a molecule of butane, C4H10?

A 3 B 10 C 13 D 14

35 Propane reacts with chlorine in a substitution reaction.

Which reaction condition is required for the reaction to occur?

A acid catalyst
B iron catalyst

C temperature of 400 C
D ultraviolet light

36 The structure of an organic compound is shown.

H H H

H C C C O H

H H H

Which structure represents a molecule that reacts with steam to produce this product?

A B C D

H H H H H H H H H H

C C H C C C H H C C O H H C C C

H H H H H H H H H

37 Which term describes nylon?

A addition polymer
B natural polymer
C polyamide
D polyester

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38 Ethene can be polymerised.

Which diagram represents the structure of the product formed?

A B C D

H H H H H H H H H H

C C C C C C H C C C C H

H H H H n H H n H H H H

39 An acid–base titration is described.

● 25.0 cm3 of dilute aqueous alkali is put into a conical flask.

● Indicator is added to the flask.
● Dilute acid is added to the aqueous alkali until the indicator changes colour.
● The volume of acid used is then recorded.

Which use of apparatus is correct?

A The 25.0 cm3 of aqueous alkali is measured using a volumetric pipette.

B The 25.0 cm3 of aqueous alkali is measured using the lines on the conical flask.
C The volume of acid is measured using a measuring cylinder.
D The volume of acid is measured using a volumetric pipette.

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40 Substance Q is investigated using chromatography.

The chromatogram is shown. The diagram is not drawn to scale.

solvent front

129 mm
114 mm

83 mm

baseline
13 mm Q

What is the Rf value of Q?

A 0.60 B 0.64 C 0.69 D 0.72

Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.

To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge
Assessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download
at www.cambridgeinternational.org after the live examination series.

Cambridge Assessment International Education is part of Cambridge Assessment. Cambridge Assessment is the brand name of the University of Cambridge
Local Examinations Syndicate (UCLES), which is a department of the University of Cambridge.

© UCLES 2023 0620/22/O/N/23

 Cambridge IGCSE™

PHYSICS 0625/22
Paper 2 Multiple Choice (Extended) October/November 2023
45 minutes

You must answer on the multiple choice answer sheet.

*8476352557*

You will need: Multiple choice answer sheet

Soft clean eraser
Soft pencil (type B or HB is recommended)

INSTRUCTIONS
 There are forty questions on this paper. Answer all questions.
 For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
 Follow the instructions on the multiple choice answer sheet.
 Write in soft pencil.
 Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
 Do not use correction fluid.
 Do not write on any bar codes.
 You may use a calculator.
 Take the weight of 1.0 kg to be 9.8 N (acceleration of free fall = 9.8 m / s2).

INFORMATION
 The total mark for this paper is 40.
 Each correct answer will score one mark.
 Any rough working should be done on this question paper.

This document has 16 pages. Any blank pages are indicated.

IB23 11_0625_22/4RP
© UCLES 2023 [Turn over
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1 Which quantity is a scalar quantity?

A acceleration
B force
C time
D velocity

2 A student measures the average speed of a cyclist in a race.

Which quantities must she measure?

A the total time taken to complete the race and the time taken for the cyclist to reach her
highest speed
B the total time taken to complete the race and the total distance travelled by the cyclist at her
highest speed
C the total time taken to complete the race and the total distance travelled by the cyclist
D the time taken to reach her highest speed and the total distance travelled by the cyclist

3 The diagram shows a series of images of a moving object taken at regular intervals.

The object is moving from left to right.

Which statement describes the motion of the object?

A The object accelerates continuously.

B The object decelerates continuously.
C The object travels at constant speed and then accelerates.
D The object travels at constant speed and then decelerates.

4 A plastic ball has a mass of 4.0 g and a volume of 20 cm3.

There is a crack in the ball’s surface.

The ball is placed in a bath of water. Water leaks into the ball without changing the volume of the
ball and eventually the ball sinks.

The density of water = 1.0 g / cm3.

Which mass of water has entered the ball when the top of the ball is first level with the water
surface?

A 5.0 g B 16 g C 20 g D 24 g

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5 A satellite orbits the Earth at constant speed in a circular orbit.

Which statement is correct?

A The resultant force on the satellite is zero.

B The resultant force on the satellite is towards the Earth.
C The resultant force on the satellite is away from the Earth.
D The resultant force on the satellite is in the direction of its motion.

6 The diagrams show four identical objects. Each object is acted on by only the forces shown.

Which diagram shows an object in equilibrium?

A B C D

10 N 10 N 10 N 10 N 10 N 20 N

10 N 10 N

20 N 10 N 10 N 10 N

7 A resultant force F accelerates a car of mass m along a straight horizontal road from rest to a
speed v in time t, giving it momentum p.

Which pair of relationships for this situation is correct?

A pt = mv and F = pt
B p = mv and F = pt
C p = mv and Ft = p
D p = mvt and Ft = v

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8 The diagram shows part of a rollercoaster ride with the car at different positions.

The car runs freely down from position X to position Y and up the hill on the other side.

car
X

What happens to the energy in the kinetic store and the gravitational potential store of the car as
it moves from position X to position Y?

energy in
energy in
gravitational
kinetic store
potential store

A decreases decreases
B decreases increases
C increases decreases
D increases increases

9 A box is initially at rest at the top of a rough slope.

The box slides down the slope.

The weight of the box is 20 N.

The slope is 4.0 m long and 2.0 m high.

4.0 m
2.0 m

The box does 10 J of work against friction as it slides down the slope.

What is the speed of the box as it reaches the bottom of the slope?

A 5.4 m / s B 6.3 m / s C 7.1 m / s D 9.5 m / s

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10 An electric car is charged overnight. In 8.0 hours, 180 MJ of energy is transferred.

What is the power of the charger?

A 6.3 kW B 380 kW C 23 MW D 1400 MW

11 An object is a depth h below the surface of a liquid. The pressure due to the liquid at this depth is
p. The gravitational field strength is g.

What is the density  of the liquid?

pg ph p
A  = pgh B = C = D =
h g hg

12 Brownian motion is the random motion of particles.

In which states of matter is Brownian motion observed?

A gases, liquids and solids

B gases and liquids only
C gases and solids only
D liquids and solids only

13 The volume of a fixed mass of gas is varied. The temperature remains constant.

Which graph shows how the pressure p of the gas varies with volume V ?

A B C D

p p p p

0 0 0 0
0 V 0 V 0 1 0 1
V V

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14 Liquid evaporates from a beaker.

What happens to the temperature of the remaining liquid and how does this temperature change
affect the rate of evaporation?

rate of
temperature
evaporation

A decreases decreases
B decreases increases
C increases decreases
D increases increases

15 Thermal energy E is supplied to an object of mass m which does not change its state during the
heating process. The temperature of the object rises by T.

What is the specific heat capacity of the object?

E m T  ET  Em
A B C D
m T E m T

16 A room is heated by a radiator. The diagrams X and Y show two possible circulations of hot air,
which heat the room.

diagram X ceiling diagram Y ceiling

radiator radiator
floor floor

Which diagram and reason explain the heating of the room by convection?

diagram reason

A X air density decreases when air is heated

B X air density increases when air is heated
C Y air density decreases when air is heated
D Y air density increases when air is heated

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17 A student writes down some facts about two transverse waves.

Wave 1 has a frequency f and a velocity v.

Wave 2 has four times the frequency of wave 1 and is travelling at a velocity of 2v.

What is the wavelength of wave 2 in terms of f and v?

2f 2v v
A B 8fv C D
v f 2f

18 Straight wavefronts on the surface of a ripple tank approach a gap in a barrier. The diagram
shows how the wavefronts change shape as they pass through the gap.

barrier
straight wavefronts

What is the name of this effect?

A diffraction
B propagation
C reflection
D refraction

19 Light travels from air into glass.

What is the relationship between the refractive index n of the glass, the angle of incidence i and
the angle of refraction r ?

A n= i B n= r C n = sin i D n = sin r
r i sin r sin i

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20 Which diagram shows the image correctly formed by reflection?

A B
object image object image

mirror mirror

C D
object image object image

mirror mirror

21 A student passes parallel rays of light through four different converging lenses. He measures the
distance x and the distance y for each experiment.

Which lens has the longest focal length?

x / cm y / cm

A 4.6 2.0
B 5.1 3.1
C 5.9 2.3
D 6.1 2.4

22 The frequency of the microwaves used in a microwave oven is 2400 MHz.

What is the wavelength of these microwaves?

A 0.125 m B 8.00 m C 125 m D 7200 m

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23 Which row gives typical values for the speed of sound in a solid and in a gas?

speed of sound in a solid speed of sound in a gas

m/s m/s

A 3 30
B 30 3
C 300 3000
D 3000 300

24 A hard magnetic material can be used to make a permanent magnet.

A soft magnetic material can be used to make a temporary magnet.

Which row shows whether iron and steel are hard or soft magnetic materials?

iron steel

A hard hard
B hard soft
C soft hard
D soft soft

25 A power source is connected to a resistor XY.

X
–

+
Y

In which directions are the conventional current and the flow of free electrons through the
resistor?

conventional free electron

current flow

A X to Y X to Y
B X to Y Y to X
C Y to X X to Y
D Y to X Y to X

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26 Which unit is used to measure electromotive force (e.m.f.)?

A ampere
B joule
C volt
D watt

27 The graph shows the current–voltage characteristic for a filament lamp.

current

0
0 voltage

Which statement describes how the resistance of the lamp changes as the voltage increases?

A The resistance decreases to zero.

B The resistance decreases, but not to zero.
C The resistance increases.
D The resistance remains constant.

28 In the diagram, rod R is suspended from an insulating thread.

insulating
thread

Q
R
+ moves away
+
+
+ from rod Q
+

When the positively charged rod Q is brought close to rod R, rod R moves away from rod Q.

Which conclusion can be made from this observation?

A Rod R is charged, but it is not possible to identify the sign of the charge.
B Rod R must be positively charged.
C Rod R must be negatively charged.
D Rod R is uncharged.

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29 The circuit diagram shows a circuit used to run a d.c. motor from an a.c. supply.

Which graph shows the current in the motor?

A B
current current

0 0
0 time 0 time

C D
current current

0 0
0 time 0 time

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30 The circuit shown can be completed by inserting components at X and at Y. The completed
circuit is a potential divider in which the potential difference across component Y increases when
the temperature increases.

Y V

Which row shows the components X and Y?

X Y

A light-dependent resistor resistor

B resistor light-dependent resistor
C resistor thermistor
D thermistor resistor

31 A piece of soft iron XY has a coil of wire wound round it.

magnet soft iron

S N X Y

The N pole of a bar magnet is pulled away from end X which causes an induced current in the
coil.

The magnet is now turned round so that the N pole is on the left. It is taken to the other end of the
soft iron and the N pole is pushed towards end Y. A new current is induced in the coil.

Which statement is correct?

A The new induced current is in the opposite direction and causes the soft iron to attract the
N pole.
B The new induced current is in the opposite direction and causes the soft iron to repel the
N pole.
C The new induced current is in the same direction and causes the soft iron to attract the
N pole.
D The new induced current is in the same direction and causes the soft iron to repel the N pole.

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32 The diagram shows a wire in the magnetic field between two poles of a magnet.

magnet

N S

wire

The current in the wire repeatedly changes between a constant value in one direction and a
constant value in the opposite direction, as shown in the graph.

current

0
0 time

What is the effect on the wire?

A The force on the wire alternates between one direction and the opposite direction.
B The force on the wire is constant in size and direction.
C There is no force acting on the wire at any time.
D There is only a force on the wire when the current reverses.

33 A transformer has Np turns on its primary coil and Ns turns on its secondary coil. The voltage
across the primary coil is Vp and the voltage across the secondary coil is Vs.

What is the relationship between these four quantities?

A Vp  Vs = Np  Ns
Vp Np
B =
Vs Ns
Vp Ns
C =
Vs Np

Vp
D = Np  Ns
Vs

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34 A magnesium ion has a double positive charge and a chloride ion has a single negative charge.

Which statement is correct?

A A chlorine atom gains an electron to form the chloride ion.

B A chlorine atom loses a proton to form the chloride ion.
C A magnesium atom loses an electron to form the magnesium ion.
D A magnesium atom gains two electrons to form the magnesium ion.

35 Which row correctly describes an example of radioactive decay?

original change or
emission
nucleus no change of element

A stable  change of element

B unstable  change of element
C unstable  no change of element
D unstable  no change of element

36 A radioactive isotope of sodium has a half-life of 15 h.

The table gives data from an experiment to show how the rate of decay of the isotope varies with
time.

The background count rate has not been subtracted from these data.

time / h 0 10 20 30
count rate
400 260 170 115
counts / s

What is the background radiation count rate?

A 12 counts / s
B 15 counts / s
C 20 counts / s
D 30 counts / s

37 What happens in the process of nuclear fission?

A Electrons are added to a nucleus.

B Electrons are removed from a nucleus.
C The nucleus of an atom splits.
D Two atomic nuclei join together.

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38 The time taken for the Earth to orbit the Sun is approximately 365 days.

The average radius of the Earth’s orbit around the Sun is 1.5  108 km.

What is the average orbital speed of the Earth?

A 30 m / s

B 4.8  103 m / s

C 3.0  104 m / s

D 4.1  1010 m / s

39 The Sun transfers energy to the Earth through electromagnetic radiation.

What are two of the parts of the electromagnetic spectrum to which most of the energy belongs?

A gamma rays and X-rays

B infrared radiation and visible light
C microwaves and visible light
D radio waves and microwaves

40 How does the Sun produce its energy?

A by the fission of helium

B by the fission of hydrogen
C by the fusion of helium
D by the fusion of hydrogen

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