Cambridge A Level Chemistry 9701 — 2021 Feb/March Paper 1 · Variant 2

Question 1

1 The table shows the numbers of protons, neutrons and electrons in four different particles, W, X, Y, and Z. number of number of number of protons neutrons electrons W 32 40 32 X 32 40 34 Y 32 42 32 Z 34 40 34 Which pair represents the atoms of two isotopes of the same element? A W and Y B W and Z C X and Y D X and Z

Accepted Answer

A

Question 2

2 Where in the Periodic Table is the element that has an outer electron shell arrangement of 4s24p3? Group Period A 13 3 B 13 4 C 15 3 D 15 4

Accepted Answer

D

Question 3

3 Substance Q is a hydrocarbon. When 1.00 g of Q is completely burned, 3.22 g of carbon dioxide is produced. What could be the identity of Q? A cyclohexene B cyclopentane C ethene D pentane

Accepted Answer

A

Question 4

4 Originally, chemists thought indium oxide had the formula InO. By experiment they showed that 4.8 g of indium combined with 1.0 g of oxygen to produce 5.8 g of indium oxide. The Ar of oxygen was known to be 16. Which value for the Ar of indium is calculated using these data? A 38 B 77 C 115 D 154

Accepted Answer

B

Question 5

5 In which substance are the only intermolecular forces temporary dipole-induced dipole attractions? A hydrogen chloride B methanol C octane D water

Accepted Answer

C

Question 6

6 A solution contains 0.25 g of sulfur dioxide in 1.00 dm3 of water. Which volume of sulfur dioxide, measured at 50 C and a pressure of 1  105 Pa, must be added to 1.00 dm3 of water to produce this solution? A 0.0162 cm3 B 0.105 cm3 C 16.2 cm3 D 105 cm3

Accepted Answer

D

Question 7

7 An experiment was performed to determine the enthalpy of combustion of ethanol. thermometer test-tube water spirit burner ethanol The data collected are shown. mass of water = W g mass of ethanol burned = X g temperature rise = Y C molar mass of ethanol = Z g mol–1 specific heat capacity of water = 4.2 J K–1 g–1 Which expression can be used to calculate the enthalpy of combustion of ethanol in kJ mol–1?  4.2 WYZ  4.2 WYX  4.2 XYZ  4.2 X Y (  273) Z A B C D 1000 X 1000 Z 1000 W 1000 W

Accepted Answer

A

Question 8

8 VO2Cl reacts with NaI under acidic conditions. 2VO2Cl  +  2H2SO4  +  2NaI    VOCl 2  +  VOSO4  +  I2  +  Na2SO4  +  2H2O The oxidation state of Cl is –1 in VO2Cl and in VOCl 2. Which row about this reaction is correct? vanadium iodine A is oxidised is oxidised B is oxidised is reduced C is reduced is oxidised D is reduced is reduced

Accepted Answer

C

Question 9

9 In which reaction is water behaving as a Brønsted–Lowry base? A H2O  +  Na    NaOH  +  1 H 2 2 B H2O  +  H3PO4    H3O+  +  H2PO4 – C H2O  +  CaO    Ca(OH)2 D NH3  +  [Cu(H2O)6]2+    NH4 +  +  [Cu(H2O)5(OH)]+

Accepted Answer

B

Question 10

10 A large excess of marble chips is reacted with 25 cm3 of 1.0 mol dm–3 hydrochloric acid at 40 C. How is the result different when the reaction is repeated with 60 cm3 of 0.5 mol dm–3 hydrochloric acid at 40 C? A The reaction is faster and more of the products are made when the reaction is complete. B The reaction is faster and less of the products are made when the reaction is complete. C The reaction is slower and more of the products are made when the reaction is complete. D The reaction is slower and less of the products are made when the reaction is complete.

Accepted Answer

C

Question 11

11 The Boltzmann distribution curve for a gaseous mixture of ethene and hydrogen is shown. Nickel is an effective catalyst for the reaction that occurs. number of particles with energy, E Ea (catalysed) Ea 0 0 energy, E How does the diagram appear if the same reaction mixture is at a higher temperature? A The curve is unchanged. B The values of both Ea (catalysed) and Ea decrease. C The values of both Ea (catalysed) and Ea increase. D The values of both Ea (catalysed) and Ea remain the same.

Accepted Answer

D

Question 12

12 Which observations are made when a sample of silicon chloride, SiCl 4, is added to a beaker of water? A No visible change is observed. B Steamy fumes and a precipitate are both observed. C The appearance of a precipitate is the only observation. D The appearance of steamy fumes is the only observation.

Accepted Answer

B

Question 13

13 Which row is correct? statement reason A The first ionisation energy of phosphorus electron is lost from a is greater than that of magnesium. 3p orbital in both cases B The melting point of phosphorus phosphorus has more valence is greater than that of magnesium. electrons than magnesium C The atomic radius of phosphorus phosphorus has greater nuclear is smaller than that of magnesium. charge than magnesium D The electrical conductivity of phosphorus bonding changes from ionic in is smaller than that of magnesium. magnesium to covalent in phosphorus

Accepted Answer

C

Question 14

14 Which row correctly describes one property of barium and one property of barium oxide? observation when pH of solution obtained when barium metal is a spatula measure of BaO is added to water added to 100 cm3 of water A a few gas bubbles 8 form on the metal surface B a few gas bubbles 13 form on the metal surface C rapid effervescence is seen 8 D rapid effervescence is seen 13

Accepted Answer

D

Question 15

15 An anhydrous white salt, Z, is heated strongly for 30 minutes. A mixture of gases is given off. The solid remaining in the test-tube is then dissolved in a small volume of dilute hydrochloric acid. The addition of a few drops of dilute sulfuric acid to the test-tube causes a white precipitate to form. Which substance could be Z? A barium carbonate B barium nitrate C magnesium carbonate D magnesium nitrate

Accepted Answer

B

Question 16

16 Chlorine gas is reacted with aqueous sodium hydroxide. The oxidation number of chlorine changes from 0 to –1 and also from 0 to +1. Under which conditions does this reaction occur and what is the colour of the solid silver salt with chlorine in the oxidation state –1? reaction conditions colour of silver salt A cold, dilute alkali white B cold, dilute alkali yellow C hot, concentrated alkali white D hot, concentrated alkali yellow

Accepted Answer

A

Question 17

17 When concentrated sulfuric acid reacts with sodium iodide the products include sulfur, iodine, hydrogen sulfide and sulfur dioxide. Which statement is correct? A Hydrogen sulfide is the product of a reduction reaction. B Iodide ions are stronger oxidising agents than sulfate ions. C Sulfur atoms from the sulfuric acid are both oxidised and reduced. D Sulfur atoms from the sulfuric acid are oxidised to make sulfur dioxide.

Accepted Answer

A

Question 18

18 NO, NO2, CO and unburnt hydrocarbons are present in the exhaust gases of internal combustion engines. When catalytic converters are used to remove these compounds from the exhaust gases, redox reactions occur. What happens to each compound in the catalytic converter? unburnt NO NO2 CO hydrocarbons A oxidised oxidised reduced oxidised B oxidised oxidised oxidised oxidised C reduced reduced oxidised oxidised D reduced reduced reduced reduced

Accepted Answer

C

Question 19

19 Methylamine, CH3NH2, has similar chemical properties to ammonia, NH3. Methylamine reacts with hydrogen chloride to form a white crystalline salt, methylammonium chloride. CH3NH2  +  HCl    CH3NH3 +Cl – A sample of methylammonium chloride is heated with aqueous sodium hydroxide. What are the products? A ammonia, sodium chloride and water B ammonia, sodium hydrogencarbonate and sodium chloride C methylamine, hydrogen chloride and water D methylamine, sodium chloride and water

Accepted Answer

D

Question 20

20 The structures of citric acid and isocitric acid are shown. citric acid isocitric acid CH2CO2H CH2CO2H C(OH)CO2H CHCO2H CH2CO2H CH(OH)CO2H How many chiral centres does each acid possess? citric acid isocitric acid A 1 1 B 1 2 C 0 1 D 0 2

Accepted Answer

D

Question 21

21 How many tertiary alcohols have the molecular formula C6H14O? A 1 B 2 C 3 D 4

Accepted Answer

C

Question 22

22 The diagram shows the structure of a bromo compound that may be formed by the reaction of bromine with a hydrocarbon. CH2Br H3C C CH3 CH2Br Which row is correct? type of reaction mechanism A addition electrophilic B addition nucleophilic C substitution nucleophilic D substitution free-radical

Accepted Answer

D

Question 23

23 Part of the structure of strobilurin is shown. R and R' are inert groups. strobilurin O OCH3 R' R Strobilurin is warmed with aqueous sulfuric acid producing compound X. Compound X is then treated with hydrogen in the presence of a nickel catalyst producing compound Y. What could be the structure of compound Y? A B O OH HO OCH3 R' R' R R C D OH O OH OH OH R' R' R R OH

Accepted Answer

A

Question 24

24 Which compound produces a ketone when refluxed with an acidified solution of potassium dichromate(VI)? A pentan-1-ol B 2-methylbutan-1-ol C 2-methylbutan-2-ol D 3-methylbutan-2-ol

Accepted Answer

D

Question 25

25 Dibromopentanes can undergo ‘double elimination’ reactions to produce hydrocarbons. 2NaOH  +  C5H10Br2    C5H8  +  2NaBr  +  2H2O Which isomer produces only one hydrocarbon product? A 1,5-dibromopentane B 1,4-dibromopentane C 2,3-dibromopentane D 2,4-dibromopentane

Accepted Answer

A

Question 26

26 The diagram shows the formation of compound Y from compound X in a chemical reaction. R1 and R2 are alkyl groups. Y R1 OH KCN X  +  HCN C R2 CN Which row about this reaction is correct? mechanism compound X A electrophilic addition aldehyde B electrophilic addition ketone C nucleophilic addition ketone D nucleophilic addition aldehyde

Accepted Answer

C

Question 27

27 In this question you can assume that 1H and 3H have the same chemical properties. A sample of ethanal contains only one isotope of hydrogen, 1H. It is reduced to compound Z, C2H6O, in a nucleophilic addition reaction using NaBH4. All the hydrogen atoms in the NaBH4 are the 3H isotope. NaBH4 CH3CHO C2H6O compound Z Compound Z is then oxidised back to ethanal and water. C2H6O  +  [O]    CH3CHO  +  H2O Which statement about the final mixture of products is correct? A Both ethanal and water contain 3H atoms. B Ethanal is the only product containing 3H atoms. C Neither ethanal nor water contain 3H atoms. D Water is the only product containing 3H atoms.

Accepted Answer

A

Question 28

28 Ethanedioic acid has the formula HO2CCO2H. What is the formula of aluminium ethanedioate? A Al C2O4 B Al (C2O4)3 C Al 2C2O4 D Al 2(C2O4)3

Accepted Answer

D

Question 29

29 Which reaction gives butanoic acid as one of its products? A acid hydrolysis of butyl ethanoate B alkaline hydrolysis of butyl ethanoate C acid hydrolysis of ethyl butanoate D alkaline hydrolysis of ethyl butanoate

Accepted Answer

C

Question 30

30 When reactant X is treated with a suitable reagent, products Y and Z are formed. Infrared spectra of X, Y and Z are shown. reactant X 100 transmittance 50 0 4000 3000 2000 1000 wavenumber / cm–1 product Y product Z 100 100 transmittance transmittance 50 50 0 0 4000 3000 2000 1000 4000 3000 2000 1500 1000 500 wavenumber / cm–1 wavenumber / cm–1 Which row could be correct? X Y Z A 2,3-dimethylpent-2-ene propanone butanone B 2-methylpent-2-ene propanone propanoic acid C pent-2-ene ethanoic acid propanoic acid D propyl propanoate propan-1-ol propanoic acid

Accepted Answer

B

Question 31

31 A sample of 17.15 mol HI(g) is in dynamic equilibrium with 2.27 mol H2(g) and 2.84 mol I2(g) in a volume of 1 m3 at 764 K and 141 kPa. H2(g)  +  I2(g) 2HI(g) Two equilibrium constants, Kc and Kp, can be calculated for this mixture. Which statements about the equilibrium constants for this mixture are correct? 1 neither Kc nor Kp has any units 2 Kc = 45.6 3 Kc > Kp

Accepted Answer

B

Question 32

32 An energy cycle for the combustion of methane is shown. ∆H o CH4(g) CH4(g)  +  2O2(g) c CO2(g)  +  2H2O(l) ∆H o CH4(g) ∆H o f z C(s)  +  2H2(g)  +  2O2(g) Which expressions can be used to calculate the energy change,        ? ∆H o z 1 ∆H o CH4(g)  +  ∆H o CH4(g) f c 2 ∆H o C(s)  +  2∆H o H2(g) c c 3 ∆H o CO(g)  +  2∆H o H2(g) c c

Accepted Answer

B

Question 33

33 Many gases do not obey the general gas equation at high pressures. Why is this? 1 At higher pressures the molecules have more energy. 2 At higher pressures the volume of the molecules is a larger proportion of the total volume. 3 At higher pressures the molecules experience greater intermolecular forces.

Accepted Answer

C

Question 34

34 Which species can accept a lone pair of electrons to form a coordinate (dative covalent) bond? 1 BF3 2 H+ 3 CH3 +

Accepted Answer

A

Question 35

35 A sample containing x mol of Al 2Cl 6 is dissolved in water to give solution W. In order to precipitate all of the aluminium as its hydroxide, y mol of sodium hydroxide are required. More of the alkali is added to re-dissolve the precipitate, giving solution Z. Which statements are correct? 1 the initial pH of solution W is below 7 2 y = 3x 3 Z contains x mol of aluminium

Accepted Answer

D

Question 36

36 Nitrogen dioxide gas is produced when petrol is burned in car engines. Which acids are made in the atmosphere as a result of this release of nitrogen dioxide into the air? 1 H2SO3 2 H2SO4 3 HNO3

Accepted Answer

C

Question 37

37 In which reactions is the major product formed by a nucleophilic substitution reaction? 1 bromoethane + potassium cyanide in ethanol 2 bromoethane + ammonia in ethanol under pressure 3 bromoethane + hot concentrated sodium hydroxide in ethanol

Accepted Answer

B

Question 38

38 An excess of P reacts with Q, in the presence of concentrated sulfuric acid, to form R. Effervescence is seen when a piece of sodium is added to pure R. The structure of P is shown. P O OH OH Which organic compounds could be compound Q? O 1 OH 2 OH 3 O

Accepted Answer

B

Question 39

39 Two carbonyl compounds have the molecular formula C3H6O. Which reagents give different observations with these two compounds? 1 acidified aqueous potassium manganate(VII) 2 Fehling’s reagent 3 alkaline aqueous iodine

Accepted Answer

A

Question 40

40 An organic compound, T, does not fizz when aqueous sodium carbonate is added to it. Compound T contains 27.6% by mass of oxygen. What could be the identity of T? 1 propanal 2 ethyl butanoate 3 3-methylpentanoic acid

Accepted Answer

B

Question paper16 pages

Mark scheme3 pages

Questions as text

Q1 · The table shows the numbers of protons, neutrons and electrons in four different…

Q2 · Where in the Periodic Table is the element that has an outer electron shell arrangement…

Q3 · Substance Q is a hydrocarbon

Q4 · Originally, chemists thought indium oxide had the formula InO

Q5 · In which substance are the only intermolecular forces temporary dipole-induced dipole…

Q6 · A solution contains 0.25 g of sulfur dioxide in 1.00 dm3 of water

Q7 · An experiment was performed to determine the enthalpy of combustion of ethanol

Q8 · VO2Cl reacts with NaI under acidic conditions

Q9 · In which reaction is water behaving as a Brønsted–Lowry base?

Q10 · A large excess of marble chips is reacted with 25 cm3 of 1.0 mol dm–3 hydrochloric acid…

Q11 · The Boltzmann distribution curve for a gaseous mixture of ethene and hydrogen is shown

Q12 · Which observations are made when a sample of silicon chloride, SiCl 4, is added to a…

Q13 · Which row is correct?

Q14 · Which row correctly describes one property of barium and one property of barium oxide?

Q15 · An anhydrous white salt, Z, is heated strongly for 30 minutes

Q16 · Chlorine gas is reacted with aqueous sodium hydroxide

Q17 · When concentrated sulfuric acid reacts with sodium iodide the products include sulfur…

Q18 · NO, NO2, CO and unburnt hydrocarbons are present in the exhaust gases of internal…

Q19 · Methylamine, CH3NH2, has similar chemical properties to ammonia, NH3

Q20 · The structures of citric acid and isocitric acid are shown

Q21 · How many tertiary alcohols have the molecular formula C6H14O?

Q22 · The diagram shows the structure of a bromo compound that may be formed by the reaction of…

Q23 · Part of the structure of strobilurin is shown

Q24 · Which compound produces a ketone when refluxed with an acidified solution of potassium…

Q25 · Dibromopentanes can undergo ‘double elimination’ reactions to produce hydrocarbons

Q26 · The diagram shows the formation of compound Y from compound X in a chemical reaction

Q27 · In this question you can assume that 1H and 3H have the same chemical properties

Q28 · Ethanedioic acid has the formula HO2CCO2H

Q29 · Which reaction gives butanoic acid as one of its products?

Q30 · When reactant X is treated with a suitable reagent, products Y and Z are formed

Q31 · A sample of 17.15 mol HI(g) is in dynamic equilibrium with 2.27 mol H2(g) and 2.84 mol…

Q32 · An energy cycle for the combustion of methane is shown

Q33 · Many gases do not obey the general gas equation at high pressures

Q34 · Which species can accept a lone pair of electrons to form a coordinate (dative covalent)…

Q35 · A sample containing x mol of Al 2Cl 6 is dissolved in water to give solution W

Q36 · Nitrogen dioxide gas is produced when petrol is burned in car engines

Q37 · In which reactions is the major product formed by a nucleophilic substitution reaction?

Q38 · An excess of P reacts with Q, in the presence of concentrated sulfuric acid, to form R

Q39 · Two carbonyl compounds have the molecular formula C3H6O

Q40 · An organic compound, T, does not fizz when aqueous sodium carbonate is added to it

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