Cambridge IGCSE Chemistry (9-1) 0971 — 2020 Oct/Nov Paper 2 · Variant 2

Question 1

1 Which gas has the slowest rate of diffusion? A H2 B NH3 C CH4 D CO2

Accepted Answer

D

Question 2

2 A chromatography experiment is carried out to analyse the pigments present in four different types of leaf. The student carrying out the experiment forgot to complete his table of results, which is shown. distance number of colour of distance travelled plant travelled by pigments identified from the origin by Rf value leaf the solvent identified pigments each pigment (cm) front (cm) green green: 3.0 green: 0.81 maple F 3.7 / yellow yellow: 3.1 yellow: 0.83 green green: 2.5 green: 0.78 laurel 2 G / yellow yellow: 2.5 yellow: 0.78 green green: 2.9 green: 0.83 lime 3 / yellow 3.5 yellow: 3.0 yellow: 0.86 / orange orange: 2.7 yellow: 0.77 green green: 2.8 green: 0.80 ash 3 / yellow 3.5 yellow: 3.0 yellow: H / orange orange: 2.7 orange: 0.77 Which row identifies the values of F, G and H? F G H A 2 3.2 0.80 B 3 3.5 0.83 C 2 3.2 0.86 D 3 3.5 0.78

Accepted Answer

C

Question 3

3 Which statement about isotopes is correct? A They have different proton numbers. B They have different chemical properties. C They have the same nucleon number. D They have the same number of electrons in their outer shell.

Accepted Answer

D

Question 4

4 In the chromatography experiment shown, which label represents the solvent front? A B D C

Accepted Answer

A

Question 5

5 Different methods of separation rely on substances having different properties. Which property does distillation make use of? A boiling point B colour C particle size D solubility in different solvents

Accepted Answer

A

Question 6

6 The arrangements of the electrons in two ions formed from elements X and Y are shown. X Y n = 20 n = 20 p = 19 p = 17 Which equation represents the reaction between elements X and Y? A X2  +  2Y    2X+  +  2Y– B X2  +  2Y    2X–  +  2Y+ C 2X  +  Y2    2X+  +  2Y– D 2X  +  Y2    2X–  +  2Y+

Accepted Answer

C

Question 7

7 Which row identifies compounds that contain single covalent bonds only, double covalent bonds only or both single and double covalent bonds? single covalent bonds double covalent bonds both single and only only double covalent bonds A C2H4 CH3OH CO2 B CH3OH C2H4 CO2 C CH3OH CO2 C2H4 D CO2 C2H4 CH3OH

Accepted Answer

C

Question 8

8 Ethyl methanoate, HCOOC2H5, burns in excess oxygen to produce carbon dioxide and water. The equation is shown. 2HCOOC2H5  +  xO2    6CO2  +  6H2O What is the value of x? A 2 B 7 C 9 D 18

Accepted Answer

B

Question 9

9 Rubidium is in Group I of the Periodic Table and bromine is in Group VII. Rubidium reacts with bromine to form an ionic compound. Which row shows the electron change taking place for rubidium and the correct formula of the rubidium ion? electron change formula of ion formed A electron gained Rb+ B electron gained Rb– C electron lost Rb+ D electron lost Rb–

Accepted Answer

C

Question 10

10 Which statement explains why graphite is used as a lubricant? A All bonds between the atoms are weak. B It conducts electricity. C It has a low melting point. D Layers in the structure can slide over each other.

Accepted Answer

D

Question 11

11 The relative atomic mass of chlorine is 35.5. When calculating relative atomic mass, which particle is the mass of a chlorine atom compared to? A a neutron B a proton C an atom of carbon-12 D an atom of hydrogen-1

Accepted Answer

C

Question 12

12 Universal indicator solution is added to a neutral solution of concentrated aqueous sodium chloride. The solution, which contains H+ (hydrogen), Na+ (sodium), Cl – (chloride) and OH– (hydroxide) ions, is electrolysed. The product at the cathode is hydrogen gas and the product at the anode is chlorine gas. What happens to the colour of the indicator in the solution during electrolysis? A The colour changes from blue to green. B The colour changes from blue to red. C The colour changes from green to blue. D The colour changes from green to red.

Accepted Answer

C

Question 13

13 What is the empirical formula of an oxide of iron, formed by reacting 2.24 g of iron with 0.96 g of oxygen? A FeO B Fe2O C Fe2O3 D Fe3O4

Accepted Answer

C

Question 14

14 The combustion of methane is exothermic. CH4  +  2O2    CO2  +  2H2O Which statement about this reaction is correct? A The energy needed to break the bonds in methane and oxygen is greater than the energy released in making new bonds in carbon dioxide and water. B The energy needed to break the bonds in methane and oxygen is less than the energy released in making new bonds in carbon dioxide and water. C The energy released in breaking bonds in methane and oxygen is greater than the energy needed to make new bonds in carbon dioxide and water. D The energy released in breaking bonds in methane and oxygen is less than the energy needed to make new bonds in carbon dioxide and water.

Accepted Answer

B

Question 15

15 Hydrogen reacts with oxygen in a fuel cell. 2H2  +  O2    2H2O The reaction is exothermic. 286 kJ of energy is released for every mole of water formed. Which volume of hydrogen gas, measured at room temperature and pressure, would react with oxygen with the release of 7000 J of energy? A 587 cm3 B 1175 cm3 C 587 dm3 D 1175 dm3

Accepted Answer

A

Question 16

16 Which substance does not require oxygen in order to produce energy? A coal B hydrogen C natural gas D 235U

Accepted Answer

D

Question 17

17 Nitrogen, N2, and hydrogen, H2, can be converted into ammonia, NH3, using a catalyst. What is the purpose of the catalyst? A to increase the amount of ammonia produced B to increase the rate of reaction C to reduce the amount of reactants needed D to reduce the rate of reaction

Accepted Answer

B

Question 18

18 Ammonia is produced by the Haber process. The equation is shown. N2(g)  +  3H2(g) 2NH3(g) The forward reaction is exothermic. Which statement is correct? A Increasing pressure decreases the yield of ammonia, but speeds up the reaction. B Increasing temperature decreases the yield of ammonia, but speeds up the reaction. C Increasing the concentration of hydrogen and nitrogen results in a lower yield of ammonia. D Increasing the temperature increases the yield of ammonia and speeds up the reaction.

Accepted Answer

B

Question 19

19 During the manufacture of sulfuric acid, sulfur dioxide is converted to sulfur trioxide. 2SO2  +  O2    2SO3 Which type of reaction is this? A displacement B neutralisation C oxidation D thermal decomposition

Accepted Answer

C

Question 20

20 The equation for a redox reaction is shown. 2FeSO4  +  Cl 2  +  H2SO4    Fe2(SO4)3  +  2HCl Which element is reduced? A chlorine B iron C oxygen D sulfur

Accepted Answer

A

Question 21

21 The equation shows a reaction between aqueous hydrogen bromide and aqueous ammonia. HBr(aq)  +  NH3(aq)    NH4 +(aq)  +  Br–(aq) Which statement describes the role of aqueous hydrogen bromide? A It is a catalyst. B It is a reducing agent. C It is a proton acceptor. D It is a proton donor.

Accepted Answer

D

Question 22

22 The equations for three reactions are shown. 1 Pb(NO3)2(aq)  +  2KI(aq)    PbI2(s)  +  2KNO3(aq) 2 2AgNO3(aq)  +  CuI2(aq)    Cu(NO3)2(aq)  +  2AgI(s) 3 CuO(s)  +  H2SO4(aq)    CuSO4(aq)  +  H2O(l) Which reactions are suitable for making a salt by precipitation? A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3

Accepted Answer

A

Question 23

23 Zinc oxide is an amphoteric oxide.

Which row describes the reactions of zinc oxide?

reaction reaction
with alkalis with acids

v v

v x
x v
x x

Accepted Answer

A

Question 24

24 A student carries out an experiment to prepare pure magnesium sulfate crystals. The diagram shows the first stage of the preparation. stirrer magnesium carbonate dilute sulfuric acid He adds magnesium carbonate until no more reacts. Which process should he use for the next stage? A crystallisation B evaporation C filtration D neutralisation

Accepted Answer

C

Question 25

25 Which row about elements in the Periodic Table is correct? statement 1 statement 2 A two elements in the same group metals are on the have similar chemical properties left of the table B two elements in the same group metals are on the have similar chemical properties right of the table C two elements in the same period metals are on the have similar chemical properties left of the table D two elements in the same period metals are on the have similar chemical properties right of the table

Accepted Answer

A

Question 26

26 A new element oxfordium, Ox, was discovered with the following properties. electrical formula bonding in a solubility conduction of element molecule of Ox2 insoluble in water doesn’t conduct Ox2 Ox Ox In which group of the Periodic Table should the new element be placed? A Group III B Group V C Group VII D Group VIII

Accepted Answer

B

Question 27

27 A flammable gas needs to be removed from a tank at an industrial plant. For safety reasons, an inert gas is used. Which gas is suitable? A argon B hydrogen C methane D oxygen

Accepted Answer

A

Question 28

28 Transition elements can have variable oxidation states. Which pair of compounds shows a transition element in two different oxidation states? A Cr2O3 and Cr2(SO4)3 B Cu2O and CuCO3 C ZnS and ZnSO4 D NiO and Ni(NO3)2

Accepted Answer

B

Question 29

29 Which diagram best represents the structure of a substance that is a good conductor of electricity at 25 C? A B C D – + – + + – + – – + – +

Accepted Answer

D

Question 30

30 Why is aluminium metal unreactive with air? A It is covered with a layer of oxide. B It is low in the reactivity series. C It is produced by electrolysis of its oxide. D It melts at a high temperature.

Accepted Answer

A

Question 31

31 The apparatus used for the extraction of aluminium oxide by electrolysis is shown. carbon anodes – + carbon lining solution of as cathode aluminium oxide in molten cryolite molten aluminium collects at the bottom Which equation represents a reaction taking place at the anode? A O  +  2e–    O2– B 2O2–    O2  +  4e– C Al 3–    Al  +  3e– D Al 3+  +  3e–    Al

Accepted Answer

B

Question 32

32 The results of tests on solid S and its aqueous solution are shown. tests on solid S tests on aqueous solution of S effect of aqueous effect of effect of heat sodium hydroxide aqueous ammonia brown gas given off, white ppt., soluble in white ppt., soluble in together with a gas which excess, giving a excess, giving a relights a glowing splint colourless solution colourless solution What is S? A aluminium nitrate B aluminium sulfate C zinc sulfate D zinc nitrate

Accepted Answer

D

Question 33

33 Part of the carbon cycle is shown. combustion Q R glucose CO2 plant CH4 P What are processes P, Q and R? P Q R A decomposition respiration photosynthesis B respiration photosynthesis decomposition C respiration decomposition photosynthesis D photosynthesis respiration decomposition

Accepted Answer

B

Question 34

34 The element sulfur is found in a number of different minerals. Which mineral contains the greatest percentage by mass of sulfur? A barite, BaSO4 B galena, PbS C gypsum, CaSO4 D pyrite, FeS2

Accepted Answer

D

Question 35

35 Which structure represents a molecule of ethanol? A B C D H H H H H H H O H C C H C C H C C O H H C C H H H H H H H O H

Accepted Answer

C

Question 36

36 Which structures are structural isomers of each other? 1 2 H H H H H H H H C C C C H H C C C H H H H H H H H C H H 3 4 H H H H H H H C C C H H C C C H H H H H H C H H C H H H A 1, 2, 3 and 4 B 1, 2 and 4 only C 1 and 3 only D 2 and 4 only

Accepted Answer

C

Question 37

37 Which molecule is not produced by an addition reaction of ethene? A CH3CH3 B CH2BrCH2Br C CH3CH2OH D CH3CH2CH3

Accepted Answer

D

Question 38

38 The flow chart shows the preparation of ethanol and some important chemistry of ethanol. fermentation process Y substance X ethanol carbon dioxide  +  substance Z What are X, Y and Z? X Y Z A yeast combustion oxygen B glucose combustion steam C glucose polymerisation water D yeast fermentation glucose

Accepted Answer

B

Question 39

39 Which statement about nylon and Terylene is correct? A Nylon and Terylene are made from monomers with C=C bonds. B Nylon and Terylene contain the same linkage. C Nylon is a polyester. D Terylene is made from two different monomers.

Accepted Answer

D

Question 40

40 Which diagram represents the structure of a protein? O O O O A C C N N C C H H O O O O B C C O O C C C O O O H O H O D N C N C N C H O

Accepted Answer

D

Question paper16 pages

Mark scheme3 pages

Questions as text

Q1 · Which gas has the slowest rate of diffusion?

Q2 · A chromatography experiment is carried out to analyse the pigments present in four…

Q3 · Which statement about isotopes is correct?

Q4 · In the chromatography experiment shown, which label represents the solvent front?

Q5 · Different methods of separation rely on substances having different properties

Q6 · The arrangements of the electrons in two ions formed from elements X and Y are shown

Q7 · Which row identifies compounds that contain single covalent bonds only, double covalent…

Q8 · Ethyl methanoate, HCOOC2H5, burns in excess oxygen to produce carbon dioxide and water

Q9 · Rubidium is in Group I of the Periodic Table and bromine is in Group VII

Q10 · Which statement explains why graphite is used as a lubricant?

Q11 · The relative atomic mass of chlorine is 35.5

Q12 · Universal indicator solution is added to a neutral solution of concentrated aqueous…

Q13 · What is the empirical formula of an oxide of iron, formed by reacting 2.24 g of iron with…

Q14 · The combustion of methane is exothermic

Q15 · Hydrogen reacts with oxygen in a fuel cell

Q16 · Which substance does not require oxygen in order to produce energy?

Q17 · Nitrogen, N2, and hydrogen, H2, can be converted into ammonia, NH3, using a catalyst

Q18 · Ammonia is produced by the Haber process

Q19 · During the manufacture of sulfuric acid, sulfur dioxide is converted to sulfur trioxide

Q20 · The equation for a redox reaction is shown

Q21 · The equation shows a reaction between aqueous hydrogen bromide and aqueous ammonia

Q22 · The equations for three reactions are shown

Q23 · Zinc oxide is an amphoteric oxide

Q24 · A student carries out an experiment to prepare pure magnesium sulfate crystals

Q25 · Which row about elements in the Periodic Table is correct?

Q26 · A new element oxfordium, Ox, was discovered with the following properties

Q27 · A flammable gas needs to be removed from a tank at an industrial plant

Q28 · Transition elements can have variable oxidation states

Q29 · Which diagram best represents the structure of a substance that is a good conductor of…

Q30 · Why is aluminium metal unreactive with air?

Q31 · The apparatus used for the extraction of aluminium oxide by electrolysis is shown

Q32 · The results of tests on solid S and its aqueous solution are shown

Q33 · Part of the carbon cycle is shown

Q34 · The element sulfur is found in a number of different minerals

Q35 · Which structure represents a molecule of ethanol?

Q36 · Which structures are structural isomers of each other?

Q37 · Which molecule is not produced by an addition reaction of ethene?

Q38 · The flow chart shows the preparation of ethanol and some important chemistry of ethanol

Q39 · Which statement about nylon and Terylene is correct?

Q40 · Which diagram represents the structure of a protein?

What was in this paper

What you needed in this session

This paper, other years