Cambridge IGCSE Science - Combined 0653 — 2021 Oct/Nov Paper 2 · Variant 1
0653/21/O/N/21 · 40 questions · 40 marks · ≈45 min
The question paper and its mark scheme, free to read here and free to download. This is Cambridge’s own paper, exactly as it was sat.
Question paper16 pages
Mark scheme3 pages
Answers below. Sit the paper first if you are practising.
Questions as text
Q1 · Movement is a characteristic of all living organisms
1 Movement is a characteristic of all living organisms. Which two other characteristics of living organisms provide the energy for movement? A excretion and nutrition B growth and sensitivity C nutrition and respiration D respiration and growth
Mark scheme: C
Q2 · What are all living organisms made of?
2 What are all living organisms made of? A cells B chloroplasts C muscles D organs
Mark scheme: A
Q3 · Which statement about enzymes is correct?
3 Which statement about enzymes is correct? A They are denatured at high temperatures. B They all have an optimum pH of 7. C They all have an optimum temperature of 10 C. D They are made of carbohydrates.
Mark scheme: A
Q4 · Which letters from the list represent the balanced equation for photosynthesis?
4 Which letters from the list represent the balanced equation for photosynthesis? P C6H12O6 T H2O Q 6C6H12O6 U 6H2O R CO2 V O2 S 6CO2 W 6O2 A P + U R + V B Q + T S + U C R + T W + P D U + S P + W
Mark scheme: D
Q5 · What is an effect of iron deficiency in the diet?
5 What is an effect of iron deficiency in the diet? A anaemia B constipation C coronary heart disease D scurvy
Mark scheme: A
Q6 · The following paragraph is a description of the digestion of fats
6 The following paragraph is a description of the digestion of fats. Large pieces of fat are broken down into smaller pieces of fat by ……1…… digestion. These smaller pieces of fat can then be broken down by the enzyme ……2…… . This is ……3…… digestion. During this process, the larger molecules are broken down into smaller, ……4…… molecules. Which row correctly completes gaps 1, 2, 3 and 4? 1 2 3 4 A chemical lipase mechanical soluble B chemical protease mechanical insoluble C mechanical lipase chemical soluble D mechanical protease chemical insoluble
Mark scheme: C
Q7 · Which row correctly describes double circulation in mammals?
7 Which row correctly describes double circulation in mammals? pressure of blood pressure of blood type of blood from heart to body from heart to lungs from heart to lungs A high high oxygenated B high low deoxygenated C low high deoxygenated D low low oxygenated
Mark scheme: B
Q8 · What causes the change in breathing seen at X?
8 What causes the change in breathing seen at X? 3 X 2 volume / dm3 1 0 0 5 10 15 20 25 30 35 40 45 50 55 time / s A decreased oxygen in the blood B decreased lactic acid in the blood C increased carbon dioxide in the blood D increased sweating
Mark scheme: C
Q9 · A plant shoot is illuminated from one side only
9 A plant shoot is illuminated from one side only. What collects on the shaded side of the plant shoot? A auxin B chlorophyll C glucose D starch
Mark scheme: A
Q10 · Which part of a flower is not required for pollination?
10 Which part of a flower is not required for pollination? A anther B sepal C stamen D stigma
Mark scheme: B
Q11 · The diagram represents the human placenta
11 The diagram represents the human placenta. P blood of blood of fetus Q mother placenta P and Q show the net movement of substances. Which row identifies substances that travel in the directions of P and Q? in direction P in direction Q A blood urea B oxygen carbon dioxide C excretory products glucose D amino acids toxins
Mark scheme: C
Q12 · The diagram represents four organisms in a food chain
12 The diagram represents four organisms in a food chain. T U V W Which organisms are consumers? A T, U and V B T, U and W C T, V and W D U, V and W
Mark scheme: D
Q13 · Carbon dioxide levels in the atmosphere have risen by 30% in the last 60 years
13 Carbon dioxide levels in the atmosphere have risen by 30% in the last 60 years. Which actions have contributed to this increase? 1 burning fossil fuels 2 deforestation 3 extinction of species A 1 only B 1 and 2 only C 2 and 3 only D 1, 2 and 3
Mark scheme: B
Q14 · Which statement describes the change when water becomes ice at 0 C?
14 Which statement describes the change when water becomes ice at 0 C? A The particles collide with each other more frequently. B The particles have more kinetic energy. C The process is endothermic. D The process is exothermic.
Mark scheme: D
Q15 · Which statement explains why ionic compounds have higher melting points than covalent…
15 Which statement explains why ionic compounds have higher melting points than covalent compounds? A Attractive forces are stronger between ions than between molecules. B Ionic bonds are stronger than covalent bonds. C Ions are formed by the transfer of electrons from one atom to another. D The atoms in covalent molecules share electrons.
Mark scheme: A
Q16 · Aluminium sulfate is made when aluminium hydroxide, Al (OH)3, reacts with dilute sulfuric…
16 Aluminium sulfate is made when aluminium hydroxide, Al (OH)3, reacts with dilute sulfuric acid, H2SO4. What is the formula of aluminium sulfate? A Al SO4 B Al 2SO4 C Al 2(SO4)3 D Al 3(SO4)2
Mark scheme: C
Q17 · Hydrogen peroxide decomposes to form water and oxygen
17 Hydrogen peroxide decomposes to form water and oxygen. Which changes in temperature and in concentration both reduce the rate of this reaction? temperature of concentration of hydrogen peroxide hydrogen peroxide A decrease decrease B decrease increase C increase decrease D increase increase
Mark scheme: A
Q18 · Magnesium reacts with copper oxide
18 Magnesium reacts with copper oxide. The equation for this reaction is shown. Mg + CuO MgO + Cu Which substance is acting as an oxidising agent in this reaction? A Cu B CuO C Mg D MgO
Mark scheme: B
Q19 · Which word equation correctly describes a reaction of dilute sulfuric acid?
19 Which word equation correctly describes a reaction of dilute sulfuric acid? A sulfuric acid + zinc zinc sulfate + water B sulfuric acid + zinc carbonate zinc sulfate + carbon dioxide C sulfuric acid + zinc hydroxide zinc sulfate + water D sulfuric acid + zinc oxide zinc sulfate + hydrogen
Mark scheme: C
More questions on The characteristic properties of acids and bases
Q20 · A piece of damp blue litmus paper is placed in a gas
20 A piece of damp blue litmus paper is placed in a gas. The litmus paper turns red and then turns white. What is the gas? A carbon dioxide B chlorine C hydrogen D oxygen
Mark scheme: B
Q21 · Elements in Group I and Group VII of the Periodic Table are listed
21 Elements in Group I and Group VII of the Periodic Table are listed. Group I Group VII Li F Na Cl K Br Rb I Group I elements react with Group VII elements. Which compound is formed most vigorously? A LiF B LiI C RbF D RbI
Mark scheme: C
Q22 · Which part of the Periodic Table contains elements that are used as catalysts?
22 Which part of the Periodic Table contains elements that are used as catalysts? A Group I B Group VII C noble gases D transition metals
Mark scheme: D
Q23 · Brass is an alloy
23 Brass is an alloy. What is brass? A a compound containing two metallic elements B a compound containing two non-metallic elements C a mixture containing two metallic elements D a mixture containing two non-metallic elements
Mark scheme: C
Q24 · Four metals E, F, G and H are mixed with solutions of metal salts
24 Four metals E, F, G and H are mixed with solutions of metal salts. The results are shown. metal metal salt result H E chloride no reaction E F chloride reacts E G chloride reacts F H chloride no reaction G H chloride reacts What is the order of reactivity of these metals, from most to least reactive? A E H G F B E G H F C F H G E D F G H E
Mark scheme: B
Q25 · Carbon is used in the production of iron in a blast furnace
25 Carbon is used in the production of iron in a blast furnace. A student suggests four reasons why carbon is added to the blast furnace. 1 It is an oxidising agent. 2 It burns to produce high temperatures. 3 It removes impurities by forming slag. 4 It reacts with carbon dioxide to form carbon monoxide. Which reasons are correct? A 1 and 2 B 1 and 4 C 2 and 3 D 2 and 4
Mark scheme: D
Q26 · A student measures the masses of three unpainted and three painted iron nails
26 A student measures the masses of three unpainted and three painted iron nails. The student places the nails into separate beakers of water. water water unpainted painted iron nails iron nails After one week, the student removes the nails from the beakers, dries them and measures the masses again. Which row about the masses of the iron nails is correct? mass of mass of unpainted iron nails painted iron nails A decreased decreased B decreased unchanged C increased increased D increased unchanged
Mark scheme: D
Q27 · The fractional distillation of petroleum is shown
27 The fractional distillation of petroleum is shown. refinery gas gasoline paraffin light gas oil diesel lubricating oil petroleum bitumen Which fraction contains molecules that have the largest attractive forces? A bitumen B diesel C gasoline D refinery gas
Mark scheme: A
Q28 · The diagram shows the speed–time graph for an object that is accelerating
28 The diagram shows the speed–time graph for an object that is accelerating. 8 speed m / s 6 4 2 0 0 1 2 3 4 time / s What is the acceleration of the object and what is the distance it travels in 4.0 s? acceleration distance m / s2 / m A 1.5 20 B 1.5 32 C 2.0 20 D 2.0 32
Mark scheme: A
Q29 · A ball of mass m is thrown vertically upwards with an initial speed v
29 A ball of mass m is thrown vertically upwards with an initial speed v. The gravitational field strength is g. What is the kinetic energy of the ball when it has risen through a height h above its starting point? A 2 (mv)2 + mgh 1 B 2 (mv)2 – mgh 1 C 2 mv2 + mgh 1 D 2 mv2 – mgh 1
Mark scheme: D
Q30 · A gas loses energy and changes state to become a liquid
30 A gas loses energy and changes state to become a liquid. How do the forces between the molecules and the distances between the molecules change? forces between distances between molecules molecules A decrease decrease B decrease increase C increase decrease D increase increase
Mark scheme: C
Q31 · A student cooks a potato in a fire
31 A student cooks a potato in a fire. The student holds the potato using a metal rod. potato metal rod Which transfer of thermal energy is caused mainly by radiation? A from the fire to the air above the fire B from the fire to the student’s face C from the inside of the potato to the student’s hand D from the outside of the potato to the inside of the potato
Mark scheme: B
Q32 · A microwave oven uses microwaves with a frequency of 2.5 109 Hz
32 A microwave oven uses microwaves with a frequency of 2.5 109 Hz. What is the wavelength of these microwaves? A 0.0075 m B 0.12 m C 7.5 m D 12 m
Mark scheme: B
Q33 · A ray of light passes through a glass window
33 A ray of light passes through a glass window. Which path does it take? A air glass air B C D ray of light
Mark scheme: C
Q34 · The diagram shows a thin converging lens with focal length f
34 The diagram shows a thin converging lens with focal length f. The lens forms a magnified, upright image of an object. At which point is the object placed? lens f f f A B C D
Mark scheme: D
Q35 · Sound travels at different speeds in air, glass and water
35 Sound travels at different speeds in air, glass and water. Which list shows these three materials in the order of increasing speed of sound (slowest to fastest)? A air water glass B glass water air C water air glass D water glass air
Mark scheme: A
Q36 · There is a current of 4.0 A in a resistor
36 There is a current of 4.0 A in a resistor. How much charge passes through the resistor in 8.0 s? A 0.50 C B 2.0 C C 12 C D 32 C
Mark scheme: D
Q37 · A circuit contains a battery connected to a resistor
37 A circuit contains a battery connected to a resistor. Which values of electromotive force (e.m.f.) and resistance produce the smallest current in the circuit? e.m.f. / V resistance / A 6.0 10 B 6.0 20 C 24 80 D 24 160
Mark scheme: D
Q38 · Four wires are made from the same material but have different lengths and diameters
38 Four wires are made from the same material but have different lengths and diameters. Which wire has the smallest resistance? length diameter / cm / mm A 50 0.10 B 50 0.20 C 100 0.10 D 100 0.20
Mark scheme: B
Q39 · The diagrams show four circuits, each containing an ammeter and two lamps with different…
39 The diagrams show four circuits, each containing an ammeter and two lamps with different resistances. Which circuit shows an ammeter with a reading equal to the current in each lamp? A B C D A A A A
Mark scheme: A
Q40 · What is the purpose of a fuse in an electric circuit?
40 What is the purpose of a fuse in an electric circuit? A It acts as an extra resistor in the circuit. B It keeps the current at a steady value. C It keeps the voltage at a steady value. D It protects the circuit from a current that is too large.
Mark scheme: D
What was in this paper
The subtopics covered by these 40 questions, and how many questions each got. Open one in a new tab to see every Cambridge question on it.
3Light2Sexual reproduction in plants2Alloys and their properties1Cell structure1Circulatory systems1Corrosion of metals1Diet1Digestion1Electrical circuits1Electrical safety1Energy, work and power1Enzymes1Extraction of metals1Food chains and food webs1Formulas1Fuels1Gas exchange in humans1General properties of waves1Group I properties1Habitat destruction1Identification of ions and gases1Ions and ionic bonds1Kinetic particle model of matter1Motion1Photosynthesis1Rate of reaction1Reactivity series1Redox1Respiration1Sexual reproduction in humans1Solids, liquids and gases1Sound1The characteristic properties of acids and bases1Transfer of thermal energy1Transition elements1What you needed in this session
Cambridge’s own grade thresholds for 2021 Oct/Nov, Paper 2 · Variant 1. A higher threshold means an easier paper — the bar moves with how the cohort did.