Cambridge IGCSE Sciences - Co-ordinated (9-1) 0973 — 2020 May/June Paper 2 · Variant 2

Question 1

1 Which characteristic of living things is described as the removal of toxic materials and substances in excess of requirements? A excretion B homeostasis C nutrition D respiration

Accepted Answer

A

Question 2

2 What is not in contact with cytoplasm? A cellulose cell wall B cell membrane C chloroplast D nucleus

Accepted Answer

A

Question 3

3 A food contains reducing sugar, but no starch. What colours will be obtained if samples of the food are tested with Benedict’s solution and with iodine solution? Benedict’s test iodine test A blue blue-black B blue brown C red-orange blue-black D red-orange brown

Accepted Answer

D

Question 4

4 Why do cells contain many different types of enzymes? A Enzymes are affected by substrate concentration. B Enzymes are affected by temperature. C Enzymes have an active site complementary to a specific substrate. D Enzymes work at different pH values.

Accepted Answer

C

Question 5

5 In photosynthesis, how many molecules of glucose will be produced from twelve molecules of carbon dioxide? A 2 B 6 C 12 D 24

Accepted Answer

A

Question 6

6 Why is calcium needed in the diet? A to make carbohydrates B to make teeth C to make enzymes D to make protein

Accepted Answer

B

Question 7

7 Which is not a risk factor in coronary heart disease? A diet high in fat B low blood pressure C smoking D stress

Accepted Answer

B

Question 8

8 Which cells produce mucus in the human breathing system? A alveoli cells B capillary cells C ciliated cells D goblet cells

Accepted Answer

D

Question 9

9 What happens when the body temperature falls below normal? A Arterioles supplying the skin constrict. B Arterioles supplying the skin dilate. C Capillaries move towards the skin surface. D Capillaries move away from the skin surface.

Accepted Answer

A

Question 10

10 Which statements about individuals in a large population of birds are correct? 1 All individuals are diploid. 2 Some individuals may have the same allele combination as both of their parents. 3 Some individuals will be better adapted to their environment than others. A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3

Accepted Answer

B

Question 11

11 A farmer wants to breed sheep that will produce a high yield of milk.

What is required for breeding these sheep?

genetic selective natural
variation breeding selection
Jv v x
v x v
x v x
x x v

key
J/ = yes

X =no

Accepted Answer

A

Question 12

12 The diagram shows a food web. owl snake fox mouse frog rabbit insect plants Which statement is correct? A The fox is a secondary consumer only. B The mouse is a primary consumer only. C The owl is a tertiary consumer only. D The snake is a tertiary consumer only.

Accepted Answer

D

Question 13

13 Which line shows how the oxygen concentration of the water changes after excess fertiliser has entered a stream? A oxygen B concentration of the water C D distance downstream fertiliser run-off

Accepted Answer

B

Question 14

14 Which statement about atoms and molecules is correct? A All molecules are gases at room temperature and pressure. B An atom is the smallest part of an element. C Atoms of the same element all have the same mass. D Molecules always contain atoms of more than one element.

Accepted Answer

B

Question 15

15 What happens to rubidium atoms and to oxygen atoms when they form rubidium oxide, Rb2O? rubidium atoms oxygen atoms A gain one electron each lose one electron each B gain one electron each lose two electrons each C lose one electron each gain one electron each D lose one electron each gain two electrons each

Accepted Answer

D

Question 16

16 Which dot-and-cross diagram represents the bonding in a molecule of carbon dioxide? A B C D O C O O C O O C O O C O

Accepted Answer

A

Question 17

17 The diagram shows the electrolysis of lead(II) bromide using inert electrodes. coloured fumes electrode X electrode Y grey solid electrolyte Which statement about this experiment is correct? A Electrode X is positively charged. B The coloured fumes are produced at the negative electrode. C The electrolyte is lead(II) bromide. D The grey solid is lead(II) bromide.

Accepted Answer

C

Question 18

18 The ionic equation for the formation of chromium(III) ions is shown. Cr  →  Cr3+  +  3e– Which statement about chromium atoms is correct? A They are oxidised by gaining electrons. B They are oxidised by losing electrons. C They are reduced by gaining electrons. D They are reduced by losing electrons.

Accepted Answer

B

Question 19

19 Aluminium oxide, Al,O3, nitrogen monoxide, NO, and sulfur trioxide, SOs, are each tested with

dilute hydrochloric acid and with aqueous sodium hydroxide.

The results are shown.

oxide aqueous dilute aqueous —
hydrochloric acid sodium hydroxide
Al203 v Jv
NO x x
SO3 x Jv

Which oxides are neutral oxides?

A

B
Cc
D

Al,O3 and SO;

NO only
SO3 only

key
J/ = reaction

X = no reaction

Accepted Answer

C

Question 20

20 Zinc oxide is an insoluble base. It reacts with dilute hydrochloric acid to produce zinc chloride. Zinc chloride is soluble in water. Which statement about the preparation of zinc chloride crystals is correct? A Once the reaction is complete there is no need to filter the reaction mixture. B The reaction mixture is neutral at the point that no more zinc oxide reacts. C Zinc chloride crystals are obtained by evaporation to dryness. D Zinc chloride precipitates when the solution becomes neutral.

Accepted Answer

B

Question 21

21 The properties of the elements in Group VII of the Periodic Table change going down the group. Which change in properties is correct? A They become darker in colour. B They have lower atomic numbers. C They have lower boiling points. D They become more reactive.

Accepted Answer

A

Question 22

22 Which metal is mixed with copper to make brass? A aluminium B iron C magnesium D zinc

Accepted Answer

D

Question 23

23 Which statement is not a reason why aluminium is used in aircraft manufacture? A It forms low density alloys. B It is malleable. C It is more reactive than iron. D It is resistant to corrosion.

Accepted Answer

C

Question 24

24 Which reaction does not take place in a catalytic converter? A 2CO  +  O2  →  2CO2 B 2NO  →  N2  +  O2 C 2NO  +  2CO  →  N2  +  2CO2 D 2SO2  +  O2  →  2SO3

Accepted Answer

D

Question 25

25 Which statement about calcium carbonate is not correct? A It forms carbon dioxide when it is heated. B It forms carbon dioxide when it is mixed with dilute hydrochloric acid. C It is formed by heating lime. D It neutralises acids.

Accepted Answer

C

Question 26

26 The diagram represents the fractional distillation of petroleum. Four fractions, W, X, Y and Z, are produced. W X Y Z petroleum Which statement about fraction Y is correct? A The forces of attraction between molecules in Y are smaller than those in W. B The molecules in Y are smaller than the molecules in Z. C Y has a lower boiling point than X. D Y vapourises more readily at room temperature than W and X, but less readily than Z.

Accepted Answer

B

Question 27

27 Which row describes properties of alkenes? products of structure of molecules complete combustion A contain only carbon and hydrogen CO2 and H2O B contain only carbon and hydrogen CO and H2O C contain only single bonds CO and H2O D contain only single bonds CO2 and H2O

Accepted Answer

A

Question 28

28 A metal has a density of 20 g / cm3. A bar made of this metal has a volume of 50 cm3. What is the mass of the bar? A 0.40 g B 2.5 g C 70 g D 1000 g

Accepted Answer

D

Question 29

29 An object of mass m moving with speed v has kinetic energy E. v . A second object, also of mass m, moves with speed 2 What is the kinetic energy of the second object? E E A B C E D 2E 4 2

Accepted Answer

A

Question 30

30 Which energy resource does not have the Sun as its source of energy? A coal B geothermal C hydroelectric D waves

Accepted Answer

B

Question 31

31 A hot water tank is fitted with two identical heaters P and Q. Heater P is fitted above heater Q as shown. The tank is full of cold water. heater P heater Q When only heater Q is switched on, it takes a long time to heat the tank of water to 60 °C. What happens to the cold water when only heater P is switched on? A All the water reaches 60 °C in less time. B All the water reaches 60 °C in the same time. C The water below heater P reaches 60 °C in less time. D The water above heater P reaches 60 °C in less time.

Accepted Answer

D

Question 32

32 ‘The maximum distance a particle on the surface of deep water moves from its rest position when a wave passes it.’ Which property of a wave does this describe? A amplitude B frequency C speed D wavelength

Accepted Answer

A

Question 33

33 The diagram shows light passing through a plastic block. 55° plastic block 40° 40° 55° What is the refractive index of the plastic? A 0.73 B 0.78 C 1.27 D 1.38

Accepted Answer

C

Question 34

34 Which ray diagram represents the formation of a virtual image I of an object O? A B I O O I C D O I O I

Accepted Answer

A

Question 35

35 Two unmagnetised iron nails are in contact with the S-pole of a permanent magnet. The heads of the nails X and Y repel each other. N S X Y Why do X and Y repel? A X becomes an N-pole and Y becomes an S-pole. B X becomes an S-pole and Y becomes an N-pole. C X and Y both become N-poles. D X and Y both become S-poles.

Accepted Answer

D

Question 36

36 Which graph is the current–voltage characteristic of a filament lamp? A B current current 0 0 0 voltage 0 voltage C D current current 0 0 0 voltage 0 voltage

Accepted Answer

C

Question 37

37 There is a current of 100 mA in a circuit. How much charge flows through the circuit in 1.5 minutes? A 0.15 C B 9.0 C C 150 C D 9000 C

Accepted Answer

B

Question 38

38 A fuse is a safety device for use in an electrical circuit. The current in the circuit becomes greater than the rated value for the fuse. What happens? A The current decreases to zero. B The current decreases to the rated value for the fuse. C The thickness of the insulation around the wires increases. D The current is sent to the outer case of the appliance.

Accepted Answer

A

Question 39

39 What is the purpose of the slip rings in an alternating current (a.c.) generator? A to allow each end of the coil to contact each carbon brush alternately B to allow each end of the coil to remain in contact with the same carbon brush at all times C to maintain a constant voltage in the output circuit while the coil is rotating D to remain stationary while the coil rotates between them

Accepted Answer

B

Question 40

40 The diagrams represent the nuclei of four different atoms V, W, X and Y. V W X Y key n p n p proton p p n n n n p p p p n p p p n n neutron p n n n Which two diagrams represent isotopes of the same element? A V and Y B W and X C X and Y D Y and W

Accepted Answer

C

Question paper16 pages

Mark scheme4 pages

Questions as text

Q1 · Which characteristic of living things is described as the removal of toxic materials and…

Q2 · What is not in contact with cytoplasm?

Q3 · A food contains reducing sugar, but no starch

Q4 · Why do cells contain many different types of enzymes?

Q5 · In photosynthesis, how many molecules of glucose will be produced from twelve molecules…

Q6 · Why is calcium needed in the diet?

Q7 · Which is not a risk factor in coronary heart disease?

Q8 · Which cells produce mucus in the human breathing system?

Q9 · What happens when the body temperature falls below normal?

Q10 · Which statements about individuals in a large population of birds are correct?

Q11 · A farmer wants to breed sheep that will produce a high yield of milk

Q12 · The diagram shows a food web

Q13 · Which line shows how the oxygen concentration of the water changes after excess…

Q14 · Which statement about atoms and molecules is correct?

Q15 · What happens to rubidium atoms and to oxygen atoms when they form rubidium oxide, Rb2O?

Q16 · Which dot-and-cross diagram represents the bonding in a molecule of carbon dioxide?

Q17 · The diagram shows the electrolysis of lead(II) bromide using inert electrodes

Q18 · The ionic equation for the formation of chromium(III) ions is shown

Q19 · Aluminium oxide, Al,O3, nitrogen monoxide, NO, and sulfur trioxide, SOs, are each tested…

Q20 · Zinc oxide is an insoluble base

Q21 · The properties of the elements in Group VII of the Periodic Table change going down the…

Q22 · Which metal is mixed with copper to make brass?

Q23 · Which statement is not a reason why aluminium is used in aircraft manufacture?

Q24 · Which reaction does not take place in a catalytic converter?

Q25 · Which statement about calcium carbonate is not correct?

Q26 · The diagram represents the fractional distillation of petroleum

Q27 · Which row describes properties of alkenes?

Q28 · A metal has a density of 20 g / cm3

Q29 · An object of mass m moving with speed v has kinetic energy E

Q30 · Which energy resource does not have the Sun as its source of energy?

Q31 · A hot water tank is fitted with two identical heaters P and Q

Q32 · ‘The maximum distance a particle on the surface of deep water moves from its rest…

Q33 · The diagram shows light passing through a plastic block

Q34 · Which ray diagram represents the formation of a virtual image I of an object O?

Q35 · Two unmagnetised iron nails are in contact with the S-pole of a permanent magnet

Q36 · Which graph is the current–voltage characteristic of a filament lamp?

Q37 · There is a current of 100 mA in a circuit

Q38 · A fuse is a safety device for use in an electrical circuit

Q39 · What is the purpose of the slip rings in an alternating current (a.c.) generator?

Q40 · The diagrams represent the nuclei of four different atoms V, W, X and Y

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