Cambridge IGCSE™

CO-ORDINATED SCIENCES 0654/21

Paper 2 Multiple Choice (Extended) May/June 2023
45 minutes

You must answer on the multiple choice answer sheet.

*0220185559*

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 06_0654_21/2RP
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1 What is meant by respiration?

A protein synthesis
B sweating to lose heat
C the function of lungs
D the release of energy

2 What is meant by osmosis?

A the net movement of water molecules from a region of higher water potential to a region of
lower water potential through a cell wall
B the net movement of water molecules from a region of higher water potential to a region of
lower water potential through a partially permeable membrane
C the net movement of water molecules from a region of lower water potential to a region of
higher water potential through a cell wall
D the net movement of water molecules from a region of lower water potential to a region of
higher water potential through a partially permeable membrane

3 Linoleic acid is a fatty acid.

Which larger molecule may contain linoleic acid?

A glycogen
B oil
C protein
D starch

4 Which row about enzymes is correct?

each enzyme the active site is enzymes are

enzymes are enzymes can
catalyses many the part of the denatured at
complex work outside
different enzyme where the their optimum
carbohydrates of cells
reactions substrate binds temperature

A     
B     
C     
D     

key
 = true
 = false

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5 An experiment is set up to investigate the effect of changing the light intensity on the rate of
photosynthesis.

The lamp is moved in 10 cm intervals away from the plant and the number of bubbles of gas
recorded in 60 seconds.

move lamp away

by 10 cm intervals
up to 50 cm

bubbles

plant
lamp
beaker

ruler

What will be the result of moving the lamp further away from the beaker containing the plant?

A The number of bubbles of carbon dioxide will decrease.

B The number of bubbles of carbon dioxide will increase.
C The number of bubbles of oxygen will decrease.
D The number of bubbles of oxygen will increase.

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6 Some processes that occur in the alimentary canal and associated organs are listed.

1 absorption
2 assimilation
3 digestion
4 egestion
5 ingestion

Which diagram correctly links each process to the part of the alimentary canal or associated
organs?

A B

5 3

1 3 1 5

2 4
4 2

C D

4 5

2 3 2 3

1 1
5 4

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7 What is the sequence of blood vessels that a red blood cell passes through as it travels from the
vena cava to the kidney?

A pulmonary artery  pulmonary vein  aorta  renal artery

B pulmonary artery  pulmonary vein  aorta  renal vein

C pulmonary vein  pulmonary artery  aorta  renal artery

D pulmonary vein  pulmonary artery  aorta  renal vein

8 Which statement about anaerobic respiration is correct?

A It does not cause an oxygen debt.

B It occurs in the muscles during vigorous exercise.
C It uses oxygen to release energy from nutrient molecules.
D It releases more energy per glucose molecule compared to aerobic respiration.

9 What is the function of the cornea?

A It carries impulses to the brain.

B It controls how much light enters the pupil.
C It focuses light onto the retina.
D It refracts light.

10 In a plant, what leads to offspring that are genetically identical to the parent?

A asexual reproduction
B insect pollination
C seed germination
D sexual reproduction

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11 The diagram shows eggs and sperm containing sex chromosomes.

1 2 3 4

egg XX X XY Y

5 6 7 8

sperm X Y XX XY

Which row gives the correct combination of sex chromosomes for a male and female offspring?

male female
offspring offspring

A 1 and 8 3 and 7
B 2 and 6 2 and 5
C 3 and 8 1 and 7
D 4 and 6 2 and 5

12 The diagram shows a food web.

kestrels

wrens

bank voles goldfinches aphids caterpillars

grass hogweed ivy oak tree

How many primary consumers, secondary consumers, tertiary consumers and quaternary
consumers are present?

primary secondary tertiary quaternary

A 1 1 4 4
B 2 4 2 0
C 4 2 1 0
D 4 4 1 1

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13 What causes eutrophication?

A combustion of fossil fuels

B cutting down of forests
C discarded plastic rubbish
D overuse of nitrogen-containing fertiliser

14 An aqueous salt solution contains an insoluble impurity.

Which processes are used to obtain pure salt crystals?

A distillation then crystallisation

B distillation then chromatography
C filtration then crystallisation
D filtration then chromatography

15 The element phosphorus burns in air, as shown.

4P + 5O2  P4O10

What does the formula P4O10 show?

A a mixture of atoms of two elements

B a mixture of molecules of two elements
C a molecule of a compound
D an atom of a compound

16 Which row describes an atom that has the nucleon number 24?

number of number of number of

protons neutrons electrons

A 8 8 8
B 12 12 12
C 21 24 21
D 24 28 24

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17 Which symbol equation is not balanced?

A C3H8 + 5O2  3CO2 + 4H2O

B Fe3O4 + 2H2  3Fe + 2H2O

C Mg(OH)2 + 2HCl  MgCl 2 + 2H2O

D 2Na + 2H2O  2NaOH + H2

18 Sodium hydroxide is manufactured by the electrolysis of concentrated aqueous sodium chloride.

During the process, a gas is given off at each electrode and the aqueous sodium hydroxide
collects around one of the electrodes.

Which row identifies the gas at each electrode and the electrode around which the aqueous
sodium hydroxide collects?

electrode at which
at the anode at the cathode sodium hydroxide
collects

A chlorine hydrogen cathode

B chlorine hydrogen anode
C oxygen chlorine cathode
D oxygen chlorine anode

19 Which row explains why increasing the concentration of a reactant increases the rate of reaction?

proportion of particles collision frequency

with the minimum between reacting
energy to react particles

A increases increases
B increases stays the same
C stays the same increases
D stays the same stays the same

20 Which statements about neutralisation are correct?

1 Acids and bases produce water when they neutralise each other.
2 During neutralisation, bases transfer protons to acids.
3 Neutral solutions turn universal indicator green.
4 During neutralisation, acids transfer hydroxide ions to bases.

A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

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21 The properties of some substances are listed.

1 form acidic oxides

2 have high melting points
3 act as catalysts
4 form coloured compounds

What are the properties of transition metals?

A 1, 2 and 3 B 1, 2 and 4 C 1, 3 and 4 D 2, 3 and 4

22 Which atmospheric pollutant is removed from air by lime?

A ammonia
B carbon monoxide
C hydrocarbons
D sulfur dioxide

23 Which row describes how hydrogen and nitrogen are obtained for use in the Haber process?

hydrogen nitrogen

A electrolysis of sulfuric acid catalytic reduction of nitrogen oxides

B electrolysis of sulfuric acid distillation of air
C reaction of methane and steam catalytic reduction of nitrogen oxides
D reaction of methane and steam distillation of air

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24 Equations representing reactions in the Contact process are listed.

reaction 1 S + O2  SO2
reaction 2 2SO2 + O2 2SO3

reaction 3 H2SO4 + SO3  H2S2O7

reaction 4 H2S2O7 + H2O  2H2SO4

Which row identifies the reactions that use the stated conditions?

requires a requires a requires a

vanadium(V) oxide temperature of pressure of
catalyst 450 C 2 atmospheres

A reaction 2 reaction 1 reaction 4

B reaction 2 reaction 2 reaction 2
C reaction 3 reaction 1 reaction 2
D reaction 3 reaction 2 reaction 4

25 Which statements about limestone are correct?

1 Its main constituent is calcium oxide.

2 It can be used to manufacture lime.
3 It thermally decomposes to release carbon dioxide.
4 It is used to neutralise alkaline soils.

A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

26 Petroleum is separated into fractions by fractional distillation.

Information about uses of some fractions and positions in the fractionating column where they are
collected is shown.

fraction use position

1 gasoline making roads below refinery gas

2 bitumen petrol for car engines bottom of column
3 naphtha making chemicals below gasoline
4 refinery gas heating and cooking top of column

Which rows are correct?

A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

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27 Which structure represents the addition polymer made from the monomer propene, C3H6?

A B

CH3 H CH3 H H H H H

C C C C C C C C

H H H H H H H H

C D

CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3

C C C C C C C C

H H H H CH3 CH3 CH3 CH3

28 The diagram shows the speed–time graph for a moving object.

20
speed
m/s

10

0
0 2.0 4.0
time / s

What is the distance travelled by the object in 4.0 s?

A 30 m B 40 m C 50 m D 80 m

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29 The diagram shows a triangular sheet of metal with sides of length 50 cm, 40 cm and 30 cm. The
sheet is free to move about a pivot at the top corner, as shown.

pivot

50 cm
40 cm

5.0 N
30 cm

A cord is attached to the bottom left corner of the sheet and pulled with a horizontal force of 5.0 N
to the left.

What is the moment of the 5.0 N force about the pivot?

A 150 N cm B 200 N cm C 250 N cm D 600 N cm

30 A machine has useful output energy of 1000 J and wasted energy of 300 J.

Which expression is used to calculate the efficiency of the machine?

A 300  100%
1000  300

B 300  100%
1000

1000  300
C  100%
1000

D 1000  100%
1000  300

31 Which statement about thermal radiation is correct?

A A dull surface is a good absorber and a good reflector of thermal radiation.

B A dull surface is a poor absorber and a poor reflector of thermal radiation.
C A shiny surface is a good absorber but a poor reflector of thermal radiation.
D A shiny surface is a poor absorber but a good reflector of thermal radiation.

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32 A student stands in front of a plane mirror on a wall.

Which statement about the image of the student is not correct?

A The image is laterally inverted (left to right).

B The image is smaller than the student.
C The image is upright.
D The student and the image are equal distances from the mirror.

33 A wave has a frequency of 3.0 MHz and a speed of 1500 m / s.

What is the wavelength of the wave?

A 5.0  10–4 m B 0.50 m C 500 m D 4500 m

34 The diagram shows a ray of light passing from air into plastic. The sizes of four angles are given.

30°

60°
air
plastic
72°

18°

The table gives the value of the sine of each angle.

angle /  sine

18 0.31
30 0.50
60 0.87
72 0.95

What is the refractive index of the plastic?

A 0.62 B 0.92 C 1.6 D 1.7

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35 Two insulators are charged by rubbing them with a cloth.

After this, the charged insulators repel each other.

Which statement is a possible description of how the insulators become charged?

A One gained electrons and the other gained protons.

B One gained electrons and the other lost electrons.
C They both lost electrons.
D They both lost protons.

36 A battery of e.m.f. V is connected across a resistor of resistance R. There is a current in the

resistor.

current

Which row shows two changes that both increase the current in the resistor?

change 1 change 2

A decrease V decrease R
B decrease V increase R
C increase V decrease R
D increase V increase R

37 An electric kettle is connected to a 250 V supply. The current in the heating element of the kettle
is 10 A.

How much electrical energy is transferred in 3.0 minutes?

A 75 J B 4500 J C 7500 J D 450 000 J

38 Fuses are used in domestic electric circuits.

Which statement about fuses is correct?

A A fuse is connected in the live wire.

B A fuse is connected in the neutral wire.
C A 3.0 A fuse produces a current of exactly 3.0 A in the circuit.
D A 3.0 A fuse produces a minimum current of 3.0 A in the circuit.

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238
39 A radioactive nucleus 92 U decays into a thorium (Th) nucleus by emitting an alpha-particle.

What is the symbol for the thorium nucleus formed?

234 234 238 238
A 90 Th B 92 Th C 90 Th D 92 Th

40 The diagrams show a beam of beta-particles passing into an electric field and another beam of
beta-particles passing into a magnetic field.

+ + + + +
beta-particles

– – – – –

N
beta-particles

In which direction is the beam deflected in each case?

electric field magnetic field

A towards the negative plate into the page

B towards the negative plate out of the page
C towards the positive plate into the page
D towards the positive plate out of the page

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 0654/21/M/J/23

 The Periodic Table of Elements
Group

© UCLES 2023
I II III IV V VI VII VIII
1 2
H He
hydrogen helium
Key 1 4
3 4 atomic number 5 6 7 8 9 10

Li Be atomic symbol B C N O F Ne
lithium beryllium name boron carbon nitrogen oxygen fluorine neon
7 9 relative atomic mass 11 12 14 16 19 20
11 12 13 14 15 16 17 18
Na Mg Al Si P S Cl Ar
sodium magnesium aluminium silicon phosphorus sulfur chlorine argon
23 24 27 28 31 32 35.5 40
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton
39 40 45 48 51 52 55 56 59 59 64 65 70 73 75 79 80 84
37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon
16

85 88 89 91 93 96 – 101 103 106 108 112 115 119 122 128 127 131
55 56 57–71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86

0654/21/M/J/23
lanthanoids
Cs Ba Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
caesium barium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon
133 137 178 181 184 186 190 192 195 197 201 204 207 209 – – –
87 88 89–103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118
actinoids
Fr Ra Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
francium radium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson
– – – – – – – – – – – – – – – – –

57 58 59 60 61 62 63 64 65 66 67 68 69 70 71
lanthanoids La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium
139 140 141 144 – 150 152 157 159 163 165 167 169 173 175
89 90 91 92 93 94 95 96 97 98 99 100 101 102 103
actinoids Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr
actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium
– 232 231 238 – – – – – – – – – – –

The volume of one mole of any gas is 24 dm3 at room temperature and pressure (r.t.p.).