Cambridge A Level Chemistry 9701 — 2025 May/June Paper 1 · Variant 4

Question 1

1 The diagram shows the logarithm of the first 13 ionisation energies of an element. log ionisation energy 1 2 3 4 5 6 7 8 9 10 11 12 13 number of electrons removed Which statement is correct? A A proton is lost for each successive ionisation energy. B The element is aluminium. C The element is silicon. D The element has only one outer electron.

Accepted Answer

C

Question 2

2 What is the empirical formula of butanoic acid? A C2H4O B C3H6O C C4H8O D C5H10O

Accepted Answer

A

Question 3

3 In which pair is the bond angle in the first species smaller than the smallest bond angle in the second species? A CH4 and SF6 B CO2 and BF3 C H2O and H3O+ D NH4 + and NH3

Accepted Answer

C

Question 4

4 Two glass vessels, M and N, are connected by a closed valve. M N M contains helium at 20 C at a pressure of 1  105 Pa. N has been evacuated, and has three times the volume of M. The valve is opened and the temperature of the whole apparatus is raised to 100 C. What is the final pressure in the system? A 3.18  104 Pa B 4.24  104 Pa C 1.25  105 Pa D 5.09  105 Pa

Accepted Answer

A

Question 5

5 Solid sulfur consists of molecules made up of eight atoms covalently bonded together. The bonding in sulfur dioxide is O=S=O. enthalpy change of combustion of S8,        S8(s) = –2376 kJ mol–1 energy required to break 1.0 mol S8(s) into gaseous atoms = 2232 kJ mol–1 O=O bond enthalpy = 496 kJ mol–1 Using these data, what is the value of the S=O bond enthalpy? A 239 kJ mol–1 B 257 kJ mol–1 C 319 kJ mol–1 D 536 kJ mol–1

Accepted Answer

D

Question 6

6 In this question, the average oxidation state of sulfur in S2O3 2– and sulfur in S2O4 2– should be used. In which reaction does the underlined element have the largest increase in oxidation state? A 3CrO4 3–(aq)  +  8H+(aq)    2CrO4 2–(aq)  +  Cr3+(aq)  +  4H2O(l) B 2NO2(g)  +  H2O(l)    HNO3(aq)  +  HNO2(aq) C S2O3 2–(aq)  +  2H+(aq)    S(s)  +  SO2(g)  +  H2O(l) D 2S2O4 2–(aq)  +  H2O(l)    S2O3 2–(aq)  +  2HSO3 –(aq)

Accepted Answer

C

Question 7

7 Methanol, CH3OH, is made industrially from carbon monoxide and hydrogen in the equilibrium reaction shown. CO(g)  +  2H2(g) CH3OH(g) H = –100 kJ mol–1 Which statement about this equilibrium is correct? p A Kp for the process is CH 3 OH . p  p CO H 2 B An increase in pressure increases the equilibrium yield of methanol. C An increase in temperature increases the equilibrium yield of methanol. D The addition of an effective catalyst increases the equilibrium yield of methanol.

Accepted Answer

B

Question 8

8 The distribution of molecular energies in an ideal gas can be represented in a Boltzmann distribution. Which change in conditions leads to a larger value for the number of molecules that have the most probable energy? A keeping the temperature constant but decreasing the pressure B keeping the pressure constant but decreasing the temperature C keeping the temperature constant but increasing the pressure D keeping the pressure constant but increasing the temperature

Accepted Answer

B

Question 9

9 Which graph represents the number of unpaired electrons in the atoms of six elements in Period 3 of the Periodic Table? A B number of number of unpaired unpaired electrons electrons 0 0 13 14 15 16 17 18 13 14 15 16 17 18 proton number proton number C D number of number of unpaired unpaired electrons electrons 0 0 13 14 15 16 17 18 13 14 15 16 17 18 proton number proton number

Accepted Answer

D

Question 10

10 A 69.0 g sample of nitrogen dioxide is placed in a reaction vessel. The initial pressure of the nitrogen dioxide is P. An effective catalyst is then added and the nitrogen dioxide begins to decompose into its elements. After ten minutes, the total pressure is 1.1P. What is the mass of oxygen molecules in the reaction vessel after ten minutes? A 4.80 g B 9.60 g C 38.4 g D 48.0 g

Accepted Answer

B

Question 11

11 Which statement about the molecule PF5 is correct? A Every F–P–F bond angle is 90. B The central atom in the molecule does not have a lone pair of electrons. C The molecule has an overall dipole moment. D The shape of the molecule is octahedral.

Accepted Answer

B

Question 12

12 Which solid compound has both ionic and covalent bonding but not coordinate bonding? A Al 2Cl 6 B CH3COONa C MgCl 2 D NH4Cl

Accepted Answer

B

Question 13

13 Which equation represents the standard enthalpy change of formation, , for ethanol? A 2C(s)  + 2 1 H (g) + 1 O2 (g)   C2H5OH(g) 2 2 2 B 2C(s)  + 2 1 H (g) + 1 O2 (g)   C2H5OH(l) 2 2 2 C 2C(s)  +  3H2(g)  + 1 O2 (g)   C2H5OH(g) 2 D 2C(s)  +  3H2(g)  + 1 O2 (g)   C2H5OH(l) 2

Accepted Answer

D

Question 14

14 When K2MnO4 reacts with concentrated hydrochloric acid, the products include chlorine molecules and MnCl 2. All of the manganese atoms are reduced to MnCl 2. Both Mn and Cl change their oxidation numbers during the reaction. No other element is oxidised or reduced. Using these changes in oxidation number, how many moles of chlorine will be produced when 1.0 mol of K2MnO4 reacts with an excess of hydrochloric acid? A 2.0 mol B 2.5 mol C 3.0 mol D 4.0 mol

Accepted Answer

A

Question 15

15 A nitrogen–hydrogen mixture, initially in the mole ratio of 1 : 3, reaches equilibrium with ammonia when 50% of the nitrogen has reacted. The total final pressure is p. N2  +  3H2 2NH3 What is the partial pressure of ammonia in the equilibrium mixture? p p p p A B C D 6 4 3 2

Accepted Answer

C

Question 16

16 Propyl methanoate is hydrolysed with NaOH(aq) at 20 C to form two products, X and Y. Product X is an alcohol. Data from the experiment is shown. time / s [X] / mol dm–3 0 0.000 40 0.004 80 0.007 120 0.010 180 0.015 240 0.019 300 0.022 Which row is correct? average rate of reaction product Y between 240 and 300 s A 5.00  10–5 mol dm–3 s–1 HCOONa B 5.00  10–5 mol dm–3 s–1 HCOOH C 7.33  10–5 mol dm–3 s–1 HCOONa D 7.33  10–5 mol dm–3 s–1 HCOOH

Accepted Answer

A

Question 17

17 The table shows the numbers of bond pairs and lone pairs in four different species. Which row is correct? total number total number species of bond pairs of lone pairs A nitrogen molecule 3 1 B ammonia molecule 4 1 C ammonium ion 4 0 D hydroxide ion 1 4

Accepted Answer

C

Question 18

18 Which row is correct? property explanation A AgI dissolves in aqueous ammonia AgI reacts with more readily than AgCl does aqueous ammonia B HCl decomposes Cl is more more readily than HI does electronegative than I C I2 has a higher I2 has stronger melting point than Cl 2 van der Waals’ forces than Cl 2 D I2 is a stronger oxidising an I atom loses electrons agent than Cl 2 more readily than a Cl atom

Accepted Answer

C

Question 19

19 Substance J reacts with water. A gas is given off and the pH of the solution increases. The solution is then reacted with sulfuric acid and a white precipitate forms. What could be substance J? A barium B barium oxide C magnesium D magnesium oxide

Accepted Answer

A

Question 20

20 Compound L has empirical formula NH. It decomposes on gentle heating to produce ammonia and compound M only. An aqueous solution of compound L is a good conductor of electricity. Which row could be correct? species present identity of M in L(aq) A N2H4 N3– and H+ B N2H4 NH4 + and NH2 – C HN3 NH3 and HN3 D HN3 NH4 + and N3 –

Accepted Answer

D

Question 21

21 X, Y and Z are elements in Period 3 of the Periodic Table. The results of some experiments carried out with compounds of these elements are shown. result of adding result of adding result of adding element the oxide of the the chloride of the the oxide of the element to H2O(l) element to H2O(l) element to HCl (aq) X no reaction hydrolyses forms chloride salt Y forms hydroxide dissolves forms chloride salt Z forms acid hydrolyses hydrolyses Which statement is correct? A Element X is Al and element Y is Mg. B Element X is Si and element Y is Na. C Element Y is Al and element Z is P. D Element Y is Na and element Z is Al .

Accepted Answer

A

Question 22

22 The flow diagram shows two successive reactions starting from element Q. Element Q is either calcium or barium. 1 heat with oxygen element Q compound R 2 add to water Element Q forms a nitrate that is less thermally stable than strontium nitrate. What is the identity of compound R? A CaO B Ca(OH)2 C BaO D Ba(OH)2

Accepted Answer

B

Question 23

23 Which anions are formed when chlorine is passed into cold aqueous potassium hydroxide? A Cl – and Cl O– B Cl – and Cl O3 – C Cl – and Cl O4 – D Cl O– and Cl O3 –

Accepted Answer

A

Question 24

24 What increases for each successive element in Period 3 from sodium to sulfur? A the highest oxidation number of the element seen in an oxide B the melting point of the elements C the number of occupied orbitals in the atom D the pH of the solutions of the chlorides in water

Accepted Answer

A

Question 25

25 Which statement about an ammonium ion is correct? A All of the H–N–H bond angles in the ion are 90. B All of the H–N–H bond angles in the ion are 107. C The ion contains a N–H dative covalent bond which is weaker than the other three N–H covalent bonds. D The ion will react with a base as it is a weak acid.

Accepted Answer

D

Question 26

26 An alcohol, U, is reacted with hot acidified K2Cr2O7 solution. The organic product of the reaction contains 58.8% C, 9.8% H and 31.4% O by mass. What is the identity of alcohol U? A 2-methylbutan-2-ol B 3-methylbutan-2-ol C pentan-1-ol D propan-1-ol

Accepted Answer

C

Question 27

27 Which row shows a primary, a secondary and a tertiary alcohol? primary secondary tertiary CH2OH CH2OH CH2OH A CH2 CHOH CHOH CH3 CH3 CH2OH CH2OH CH3 CH3 B CH3 C H CH3 C OH CH3 C H CH3 CH3 CH2OH CH2OH CH2OH CH2OH C CH3 C H CH3 C CH2OH CH3 C CH2OH H H CH2OH H CH3 CH3 D CH3 C OH CH3 C OH CH3 C OH H H CH3

Accepted Answer

D

Question 28

28 1-chloro-2-methylbutane reacts with sodium cyanide in a nucleophilic substitution reaction. What is the most likely intermediate or transition state in this reaction? A B – – H H H3C CH2CH3 NC C Cl NC C Cl CH(CH3)CH2CH3 CH3 C D H3C CH2CH3 H H +C +C CH3 CH(CH3)CH2CH3

Accepted Answer

A

Question 29

29 When 0.010 mol of a hydrocarbon X reacts with 720 cm3 of hydrogen at room conditions, an alkane is formed. What is hydrocarbon X? A B C D

Accepted Answer

C

Question 30

30 An alkene reacts with hot concentrated acidified KMnO4 to produce a single organic product as shown. hot concentrated O O acidified KMnO4(aq) alkene OH What is the structure of the alkene? A B C D

Accepted Answer

D

Question 31

31 Testosterone is an optically active organic molecule. testosterone OH O How many chiral centres are there in one molecule of testosterone? A 5 B 6 C 7 D 8

Accepted Answer

B

Question 32

32 Quinone is an unsaturated molecule. quinone O O Which statement about quinone is correct? A Quinone is non-planar and has an overall dipole moment. B Quinone is non-planar and does not have an overall dipole moment. C Quinone is planar and has an overall dipole moment. D Quinone is planar and does not have an overall dipole moment.

Accepted Answer

D

Question 33

33 Which reagent would react with 1-bromopropane to give the highest yield of propene? A ammonia B aqueous potassium hydroxide C potassium cyanide D ethanolic sodium hydroxide

Accepted Answer

D

Question 34

34 Acidified potassium dichromate(VI), K2Cr2O7, is added to propan-1-ol and the mixture is immediately distilled. The distillate is treated with HCN in the presence of KCN. What is the organic product? A CH3C(CN)(OH)CH3 B CH3CH2CH2CO2H C CH3CH2CH(OH)CN D CH3CH2CH2CN

Accepted Answer

C

Question 35

35 Compound Q gives positive results when tested separately with alkaline I2(aq) and with Tollens’ reagent. What is compound Q? A CHOCH2CH2CHO B CH3CH2COCHO C CH3COCH2CHO D CH3COCOCH3

Accepted Answer

C

Question 36

36 Structural isomerism and stereoisomerism should be considered when answering this question. How many isomeric esters of methanoic acid can be made with the molecular formula C5H10O2? A 2 B 3 C 4 D 5

Accepted Answer

D

Question 37

37 The juice of one lemon reacts completely with 120 cm3 of 0.50 mol dm–3 sodium carbonate solution. The formula of citric acid is HOOCCH2C(OH)(COOH)CH2COOH. No sodium carbonate is left unreacted. What is the amount of citric acid in one lemon assuming that it is the only acid in the sample? A 0.02 mol B 0.04 mol C 0.06 mol D 0.09 mol

Accepted Answer

B

Question 38

38 Separate samples of 1-bromopropane are used in two different reactions. reaction 1 1-bromopropane is converted into compound X by heating it under pressure with ammonia in ethanol. reaction 2 1-bromopropane is converted into compound Y. Compound Y undergoes hydrolysis to form butanoic acid. Which row identifies compound X and describes the reagents used in reaction 2 to make compound Y? identity of compound X reagents for reaction 2 A CH3CH2CH2NH2 HCN(aq) B CH3CH2CH2NH2 KCN dissolved in ethanol C CH3CH2CH2OH HCN(aq) D CH3CH2CH2OH KCN dissolved in ethanol

Accepted Answer

B

Question 39

39 The diagram shows part of a polymer chain. H H CN H H H CN H C C C C C C C C CN H H H CN H H H Which monomer would form this polymer? A B C D H H H CN H CN H H H CN H C C C C C C C C C C C C H CN CN H H CN H CN H

Accepted Answer

A

Question 40

40 The mass spectrum of element Z is shown. 100 relative 50 intensity 0 30 35 40 45 50 55 60 65 70 75 80 m / e What is element Z? A arsenic B chlorine C gallium D tungsten

Accepted Answer

B

Question paper20 pages

Mark scheme3 pages

Questions as text

Q1 · The diagram shows the logarithm of the first 13 ionisation energies of an element

Q2 · What is the empirical formula of butanoic acid?

Q3 · In which pair is the bond angle in the first species smaller than the smallest bond angle…

Q4 · Two glass vessels, M and N, are connected by a closed valve

Q5 · Solid sulfur consists of molecules made up of eight atoms covalently bonded together

Q6 · In this question, the average oxidation state of sulfur in S2O3 2– and sulfur in S2O4 2…

Q7 · Methanol, CH3OH, is made industrially from carbon monoxide and hydrogen in the…

Q8 · The distribution of molecular energies in an ideal gas can be represented in a Boltzmann…

Q9 · Which graph represents the number of unpaired electrons in the atoms of six elements in…

Q10 · A 69.0 g sample of nitrogen dioxide is placed in a reaction vessel

Q11 · Which statement about the molecule PF5 is correct?

Q12 · Which solid compound has both ionic and covalent bonding but not coordinate bonding?

Q13 · Which equation represents the standard enthalpy change of formation, , for ethanol?

Q14 · When K2MnO4 reacts with concentrated hydrochloric acid, the products include chlorine…

Q15 · A nitrogen–hydrogen mixture, initially in the mole ratio of 1 : 3, reaches equilibrium…

Q16 · Propyl methanoate is hydrolysed with NaOH(aq) at 20 C to form two products, X and Y

Q17 · The table shows the numbers of bond pairs and lone pairs in four different species

Q18 · Which row is correct?

Q19 · Substance J reacts with water

Q20 · Compound L has empirical formula NH

Q21 · X, Y and Z are elements in Period 3 of the Periodic Table

Q22 · The flow diagram shows two successive reactions starting from element Q

Q23 · Which anions are formed when chlorine is passed into cold aqueous potassium hydroxide?

Q24 · What increases for each successive element in Period 3 from sodium to sulfur?

Q25 · Which statement about an ammonium ion is correct?

Q26 · An alcohol, U, is reacted with hot acidified K2Cr2O7 solution

Q27 · Which row shows a primary, a secondary and a tertiary alcohol?

Q28 · 1-chloro-2-methylbutane reacts with sodium cyanide in a nucleophilic substitution reaction

Q29 · When 0.010 mol of a hydrocarbon X reacts with 720 cm3 of hydrogen at room conditions, an…

Q30 · An alkene reacts with hot concentrated acidified KMnO4 to produce a single organic…

Q31 · Testosterone is an optically active organic molecule

Q32 · Quinone is an unsaturated molecule

Q33 · Which reagent would react with 1-bromopropane to give the highest yield of propene?

Q34 · Acidified potassium dichromate(VI), K2Cr2O7, is added to propan-1-ol and the mixture is…

Q35 · Compound Q gives positive results when tested separately with alkaline I2(aq) and with…

Q36 · Structural isomerism and stereoisomerism should be considered when answering this question

Q37 · The juice of one lemon reacts completely with 120 cm3 of 0.50 mol dm–3 sodium carbonate…

Q38 · Separate samples of 1-bromopropane are used in two different reactions

Q39 · The diagram shows part of a polymer chain

Q40 · The mass spectrum of element Z is shown

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