Cambridge IGCSE Science - Combined 0653 — 2021 May/June Paper 2 · Variant 1
0653/21/M/J/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 · Which row correctly matches a named cell with its feature and function?
1 Which row correctly matches a named cell with its feature and function? cell feature function A ciliated cell flagellum absorbs water B palisade mesophyll cell chloroplasts transports oxygen C red blood cell large surface area phagocytosis D sperm cell flagellum reproduction
Mark scheme: D
Q2 · The diagrams represent four similar animal cells immersed in blood plasma
2 The diagrams represent four similar animal cells immersed in blood plasma. The black dots represent molecules of dissolved oxygen. Which cell will have oxygen molecules diffusing into it most rapidly? A B C D
Mark scheme: C
Q3 · Which row shows the elements that occur in all proteins?
3 Which row shows the elements that occur in all proteins? carbon hydrogen nitrogen oxygen A yes yes yes no B yes yes no yes C yes no yes yes D yes yes yes yes
Mark scheme: D
Q4 · What is the balanced equation for photosynthesis?
4 What is the balanced equation for photosynthesis? A CO2 + H2O C6H12O6 + O2 B CO2 + 6H2O 6C6H12O6 + O2 C 6CO2 + 6H2O C6H12O6 + 6O2 D 6CO2 + 12H2O 6C6H12O6 + 6O2
Mark scheme: C
Q5 · Which description of mechanical digestion is correct?
5 Which description of mechanical digestion is correct? A breakdown of food into smaller pieces with chemical change to the food molecules B breakdown of food into smaller pieces without chemical change to the food molecules C breakdown of large insoluble food molecules into small soluble food molecules D breakdown of large soluble food molecules into small soluble food molecules
Mark scheme: B
Q6 · The diagram shows a cross-section of a root hair cell
6 The diagram shows a cross-section of a root hair cell. Y X Which row identifies the part of the cell with the larger surface area and the correct function? part of cell function A X water and glucose uptake B X water and ion uptake C Y water and glucose uptake D Y water and ion uptake
Mark scheme: B
Q7 · What is the maximum number of carbon dioxide molecules produced when four glucose…
7 What is the maximum number of carbon dioxide molecules produced when four glucose molecules are used in aerobic respiration? A 6 B 12 C 24 D 48
Mark scheme: C
Q8 · What are effects of increased adrenaline production in humans?
8 What are effects of increased adrenaline production in humans? A increased rate of breathing and increased pulse rate B increased rate of breathing and narrower pupils C slower pulse rate and narrower pupils D slower pulse rate and wider pupils
Mark scheme: A
Q9 · The diagram shows a parent plant
9 The diagram shows a parent plant. parent plant Which offspring has been produced by asexual reproduction from this plant? A B C D
Mark scheme: A
Q10 · The diagram shows a flower
10 The diagram shows a flower. X What is structure X? A anther of an insect-pollinated flower B anther of a wind-pollinated flower C stigma of an insect-pollinated flower D stigma of a wind-pollinated flower
Mark scheme: D
Q11 · Materials are exchanged between the blood of the mother and embryo in the placenta
11 Materials are exchanged between the blood of the mother and embryo in the placenta. lining of maternal uterus blood placenta capillary network in placenta 1 2 embryo Which row shows the blood vessels with higher concentrations of carbon dioxide and glucose? higher concentration higher concentration of carbon dioxide of glucose A 1 1 B 2 2 C 2 1 D 1 2
Mark scheme: D
Q12 · The diagram shows a food web
12 The diagram shows a food web. eagle fox small bird goat ant caterpillar locust beetle grass wildflower tree Which row states the number of species of each category in this food web? number of primary number of secondary number of tertiary consumer species consumer species consumer species A 6 1 1 B 5 2 1 C 5 2 2 D 3 4 3
Mark scheme: B
Q13 · Which process takes carbon dioxide out of the air?
13 Which process takes carbon dioxide out of the air? A combustion B decomposition C photosynthesis D plant respiration
Mark scheme: C
Q14 · A fixed mass of argon gas in a sealed container is heated
14 A fixed mass of argon gas in a sealed container is heated. The pressure inside the container increases. Which statement explains why the pressure increases? A There is an increase in the number of gaseous particles inside the container. B There is an increase in the number of collisions per second between the particles of gas and the walls of the container. C The particles of gas have less energy and collide with the wall of the container more frequently. D There is a decrease in the space that the particles have to move in.
Mark scheme: B
Q15 · What is an example of a physical change?
15 What is an example of a physical change? A carbon dioxide turning limewater milky B the crystallisation of copper(II) sulfate from solution C the electrolysis of molten lead(II) bromide D the thermal decomposition of calcium carbonate
Mark scheme: B
Q16 · Which row about elements and compounds is correct?
16 Which row about elements and compounds is correct? elements compounds A are metals only contain ionic or covalent bonds B are non-metals only contain covalent bonds only C are metals or non-metals contain ionic bonds only D are metals or non-metals contain ionic or covalent bonds
Mark scheme: D
Q17 · The symbols and charges of some ions are shown
17 The symbols and charges of some ions are shown. ● aluminium, Al 3+ ● phosphate, PO4 3– ● sodium, Na+ ● sulfate, SO4 2– What are the formulae of aluminium sulfate and sodium phosphate? aluminium sodium sulfate phosphate A Al 2(SO4)3 Na3PO4 B Al 2(SO4)3 Na(PO4)3 C Al 3(SO4)2 Na3PO4 D Al 3(SO4)2 Na(PO4)3
Mark scheme: A
Q18 · Two substances are electrolysed separately using inert electrodes
18 Two substances are electrolysed separately using inert electrodes. Which two substances form the same product at one of the electrodes? A molten sodium bromide and concentrated aqueous sodium chloride B molten sodium bromide and dilute sulfuric acid C molten aluminium oxide and concentrated aqueous sodium chloride D molten aluminium oxide and dilute sulfuric acid
Mark scheme: D
Q19 · An energy diagram for a reaction is shown
19 An energy diagram for a reaction is shown. energy progress of reaction Which statement about the reaction is not correct? A Activation energy is needed to start the reaction. B The overall energy change is endothermic. C The surroundings increase in temperature during the reaction. D The reaction could be a combustion reaction.
Mark scheme: B
Q20 · In the reaction between an acid and a metal, the rate of reaction decreases as the…
20 In the reaction between an acid and a metal, the rate of reaction decreases as the reaction proceeds. A student suggests three reasons why the rate of this reaction decreases. 1 The concentration of the acid decreases as it gets used up. 2 The energy needed to break bonds is used up as the products form. 3 The surface area of the metal decreases as it gets smaller. Which reasons are correct? A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only
Mark scheme: C
Q21 · The solubilities of some copper compounds are shown
21 The solubilities of some copper compounds are shown. copper compound solubility in water copper nitrate soluble copper sulfate soluble copper oxide insoluble copper hydroxide insoluble Which method is used to make copper sulfate? A Mix aqueous copper hydroxide and dilute sulfuric acid. B Mix aqueous copper nitrate with aqueous sodium sulfate and filter off solid copper sulfate. C Mix excess aqueous copper nitrate with dilute sulfuric acid and filter off unreacted copper nitrate. D Mix excess solid copper oxide with dilute sulfuric acid and filter off unreacted copper oxide.
Mark scheme: D
Q22 · Which two substances form a white precipitate when they are mixed?
22 Which two substances form a white precipitate when they are mixed? A barium chloride and hydrochloric acid B barium chloride and nitric acid C silver nitrate and hydrochloric acid D silver nitrate and nitric acid
Mark scheme: C
Q23 · There are eight elements in Period 3 of the Periodic Table
23 There are eight elements in Period 3 of the Periodic Table. Na Mg Al Si P S Cl Ar Which statement about the elements in this period is correct? A The elements become less metallic across the period. B The most metallic elements are at both ends of the period. C The most metallic elements are in the middle of the period. D There is no pattern in metallic character across the period.
Mark scheme: A
Q24 · The colours of concentrated aqueous solutions of Group VII elements are shown
24 The colours of concentrated aqueous solutions of Group VII elements are shown. colour of element aqueous solution fluorine colourless chlorine pale yellow bromine orange iodine red-brown Concentrated aqueous chlorine is added to colourless aqueous potassium bromide. What is the colour of the mixture? A colourless B pale yellow C orange D red-brown
Mark scheme: C
Q25 · In the blast furnace, carbon reacts with carbon dioxide to form carbon monoxide
25 In the blast furnace, carbon reacts with carbon dioxide to form carbon monoxide. C + CO2 2CO Why is this reaction essential in the extraction of iron from hematite? A Carbon monoxide is needed to reduce iron oxide. B Carbon monoxide neutralises impurities to make slag. C The reaction removes carbon impurities from the iron ore. D The reaction prevents the release of greenhouse gases.
Mark scheme: A
Q26 · Which gases may contribute to climate change when their concentrations in the air…
26 Which gases may contribute to climate change when their concentrations in the air increase? 1 carbon dioxide 2 methane 3 sulfur dioxide A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3
Mark scheme: A
Q27 · Which type of compound contains only carbon and hydrogen?
27 Which type of compound contains only carbon and hydrogen? A carbohydrate B carbonate C hydrocarbon D hydroxide
Mark scheme: C
Q28 · A boy runs up some stairs
28 A boy runs up some stairs. Which two physical quantities are used to calculate the power he develops? A his mass and his acceleration B his mass and the time taken C the work done and the time taken D the work done and the vertical distance moved
Mark scheme: C
Question 29
29 Diagram 1 is a distance–time graph. Diagram 2 and diagram 3 are speed–time graphs. distance speed speed 0 0 0 0 time 0 time 0 time diagram 1 diagram 2 diagram 3 Which of the diagrams represents the motion of an object moving with a non-zero constant acceleration? A 1 and 3 B 1 only C 2 only D 3 only
Mark scheme: D
Q30 · The diagram shows the load–extension graph for a spring
30 The diagram shows the load–extension graph for a spring. Two points on the graph are labelled X and Y. Y load / N X 10 0 0 20 extension / cm What is the spring constant of the spring and which labelled point is the limit of proportionality? spring constant limit of N/cm proportionality A 0.50 X B 0.50 Y C 2.0 X D 2.0 Y
Mark scheme: A
Q31 · Work W is done when a force F moves an object a distance d in the direction of the force
31 Work W is done when a force F moves an object a distance d in the direction of the force. Which equation gives the distance d ? d = F W d = F d = W A d = F + W B C W D F
Mark scheme: D
Q32 · Which row contains a renewable and a non-renewable energy resource in the correct column?
32 Which row contains a renewable and a non-renewable energy resource in the correct column? renewable non-renewable A geothermal wind B geothermal coal C oil wind D oil coal
Mark scheme: B
Q33 · Cold water evaporates as molecules leave it
33 Cold water evaporates as molecules leave it. Which molecules leave the water and from which part of the water do they leave? molecules that where they leave the water leave from A least energetic the surface only B least energetic throughout the water C most energetic the surface only D most energetic throughout the water
Mark scheme: C
Q34 · Copper is a good conductor of heat
34 Copper is a good conductor of heat. Plastic is a bad conductor of heat. Which statement explains this difference? A Electrons can move freely in copper but cannot move freely in plastic. B Electrons can move freely in plastic but cannot move freely in copper. C Molecules can move freely in copper but cannot move freely in plastic. D Molecules can move freely in plastic but cannot move freely in copper.
Mark scheme: A
Q35 · Which statement about waves is correct?
35 Which statement about waves is correct? A In a longitudinal wave, the vibration of the particles is perpendicular to the direction of the wave. B In a sound wave, the vibration of the particles is parallel to the direction of the wave. C Radio waves are longitudinal waves. D Sound waves are transverse waves.
Mark scheme: B
Q36 · A student uses a converging lens with a focal length F as a magnifying glass
36 A student uses a converging lens with a focal length F as a magnifying glass. What is the distance between the object and the lens? A less than F B between F and 2F C 2F D greater than 2F
Mark scheme: A
Q37 · There is a current of 20 mA in a resistor for a time t
37 There is a current of 20 mA in a resistor for a time t. During this time, a charge of 600 C passes through the resistor. What is the value of t ? A 3.3 10–5 s B 12 s C 30 s D 3.0 104 s
Mark scheme: D
Q38 · The diagram represents a circuit that includes a battery, an ammeter, a voltmeter and a…
38 The diagram represents a circuit that includes a battery, an ammeter, a voltmeter and a variable resistor. A V What happens to the readings on the meters as the resistance of the variable resistor is increased? ammeter reading voltmeter reading A decreases decreases B decreases stays constant C increases decreases D increases stays constant
Mark scheme: B
Q39 · A lamp is labelled 12 V, 25 W
39 A lamp is labelled 12 V, 25 W. How much electrical energy does the lamp transfer in 4.0 minutes when it is operating at its normal brightness? A 100 J B 1200 J C 6000 J D 72 000 J
Mark scheme: C
Q40 · An air conditioner and a television are both connected to the same electrical circuit
40 An air conditioner and a television are both connected to the same electrical circuit. X power air television supply conditioner The current in the air conditioner is 9.0 A and the current in the television is 2.0 A. Several different fuses are available. Which fuse should be connected at X? A 1 A B 3 A C 7 A D 13 A
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.
3Electrical quantities2Kinetic particle model of matter2Sexual reproduction in plants2Air quality and climate1Arrangement of elements1Biological molecules1Carbon cycle1Cell structure1Diffusion1Digestion1Drugs1Electrical circuits1Electrical safety1Electrolysis1Elements, compounds and mixtures1Exothermic and endothermic reactions1Extraction of metals1Food chains and food webs1Forces1Formulas1General properties of waves1Group VII properties1Identification of ions and gases1Light1Motion1Photosynthesis1Physical and chemical changes1Preparation of salts1Rate of reaction1Respiration1Sexual reproduction in humans1Terminology1Transfer of thermal energy1Water uptake1What you needed in this session
Cambridge’s own grade thresholds for 2021 May/June, Paper 2 · Variant 1. A higher threshold means an easier paper — the bar moves with how the cohort did.