Cambridge A Level Chemistry 9701 — 2012 May/June Paper 1 · Variant 2

Question 1

1 The molecular energy distribution curve represents the variation in energy of the molecules of a gas at room temperature. proportion of molecules 0 0 energy Which curve applies for the same gas at a lower temperature? A B proportion proportion of of molecules molecules 0 0 0 0 energy energy C D proportion proportion of of molecules molecules 0 0 0 0 energy energy

Accepted Answer

C

Question 2

2 In which species are the numbers of protons, neutrons and electrons all different? A 11 B B 19 F − C 23 Na + D 24 12Mg 2 + 5 9 11

Accepted Answer

C

Question 3

3 What is the most likely shape of a molecule of hydrazine, N2H4? A B C D H H H H H H H 90° 90° 120° 107° H N N H N N H N N N N H H H H H H

Accepted Answer

D

Question 4

4 In which species does the underlined atom have an incomplete outer shell? A Al 2Cl 6 B CH3 + C Cl 2O D H2Cl C•

Accepted Answer

B

Question 5

5 Which solid contains more than one kind of bonding? A iodine B silicon dioxide C sodium chloride D zinc

Accepted Answer

A

Question 6

6 Use of the Data Booklet is relevant to this question. The gas laws can be summarised in the ideal gas equation. pV = nRT 0.96 g of oxygen gas is contained in a glass vessel of volume 7000 cm3 at a temperature of 30 °C. What is the pressure in the vessel? A 1.1 kPa B 2.1 kPa C 10.8 kPa D 21.6 kPa

Accepted Answer

C

Question 7

7 Two moles of compound P were placed in a vessel. The vessel was heated and compound P was partly decomposed to produce Q and R. A dynamic equilibrium between chemicals P, Q and R was established. At equilibrium x moles of R were present and the total number of moles present was (2 + 2 x ). What is the equation for this equilibrium reaction? A P 2Q + R B 2P 2Q + R C 2P Q + R D 2P Q + 2R

Accepted Answer

D

Question 8

8 The value of the third ionisation energy of aluminium is 2740 kJ mol–1. Which correctly represents this statement? A Al (g) → Al 3+(g) + 3e– ∆Ho = –2740 kJ mol–1 B Al 2+(g) → Al 3+(g) + e– ∆Ho = –2740 kJ mol–1 C Al (g) → Al 3+(g) + 3e– ∆Ho = +2740 kJ mol–1 D Al 2+(g) → Al 3+(g) + e– ∆Ho = +2740 kJ mol–1

Accepted Answer

D

Question 9

9 Methanol is manufactured by reacting carbon dioxide and hydrogen. CO2(g) + 3H2(g) CH3OH(g) + H2O(g) ∆H = –49 kJ mol–1 What would increase the equilibrium yield of methanol in this process? A adding a catalyst B adding an excess of steam C increasing the pressure D increasing the temperature

Accepted Answer

C

Question 10

10 Which molecule has the largest overall dipole? A B C D H CH3 CH3 Cl H3C Cl C C O C O C C C H CH3 CH3 Cl Cl CH3

Accepted Answer

B

Question 11

11 In which substance does nitrogen exhibit the highest oxidation state? A NO B N2O C N2O4 D NaNO2

Accepted Answer

C

Question 12

12 Red lead oxide, Pb3O4, is used in metal priming paints. It can be made by heating PbO in air. 6PbO(s) + O2(g) → 2Pb3O4(s) Which two values are needed to calculate the enthalpy change for this reaction? A enthalpy change of atomisation of O2 and enthalpy change of formation of Pb3O4 B enthalpy change of formation of O2 and enthalpy change of formation of Pb3O4 C enthalpy change of formation of PbO and enthalpy change of atomisation of O2 D enthalpy change of formation of PbO and enthalpy change of formation of Pb3O4

Accepted Answer

D

Question 13

13 Which gas is present in the exhaust fumes of a car engine in a much greater amount than any other gas? A carbon dioxide B carbon monoxide C nitrogen D water vapour

Accepted Answer

C

Question 14

14 Slaked lime, Ca(OH)2, may be made from limestone, CaCO3. On heating in a lime kiln at 1000 °C, limestone decomposes as follows. reaction 1 CaCO3(s) → CaO(s) + CO2(g) Water is then reacted with calcium oxide, CaO, as follows. reaction 2 CaO(s) + H2O(l) → Ca(OH)2(s) What are the enthalpy changes of these reactions? reaction 1 reaction 2 A endothermic endothermic B endothermic exothermic C exothermic endothermic D exothermic exothermic

Accepted Answer

B

Question 15

15 The period 4 elements gallium (Ga), germanium (Ge), arsenic (As) and selenium (Se) are the elements below aluminium, silicon, phosphorus and sulfur in the Periodic Table, a portion of which is shown below. period 3 elements Al Si P S period 4 elements Ga Ge As Se The properties of each period 4 element resemble those of the period 3 element directly above it. Which period 4 elements form oxides that dissolve in water to give an acid solution? A As and Se B Ga and Ge C Ga and Se D Se only

Accepted Answer

A

Question 16

16 Chlorine shows oxidation states ranging from –1 to +7 in its compounds. What are the reagent(s) and conditions necessary for the oxidation of elemental chlorine into a compound containing chlorine in the +5 oxidation state? A AgNO3(aq) followed by NH3(aq) at room temperature B concentrated H2SO4 at room temperature C cold dilute NaOH(aq) D hot concentrated NaOH(aq)

Accepted Answer

D

Question 17

17 What can be seen when a piece of magnesium ribbon is placed in cold water? A A vigorous effervescence occurs. B Bubbles of gas form slowly on the magnesium. C The magnesium floats on the surface of the water and reacts quickly. D The magnesium glows and a white solid is produced.

Accepted Answer

B

Question 18

18 Use of the Data Booklet is relevant to this question. Sodium and sulfur react together to form sodium sulfide, Na2S. How do the atomic radius and ionic radius of sodium compare with those of sulfur? atomic radius ionic radius A sodium > sulfur sodium > sulfur B sodium > sulfur sodium < sulfur C sodium < sulfur sodium > sulfur D sodium < sulfur sodium < sulfur

Accepted Answer

B

Question 19

19 Which substance does not produce a poisonous gas, when burnt in a limited amount of air? A hydrogen B methane C propene D sulfur

Accepted Answer

A

Question 20

20 Use of the Data Booklet is relevant to this question. A sample of propyl ethanoate is hydrolysed by heating under reflux with aqueous sodium hydroxide. The two organic products of the hydrolysis are separated, purified and weighed. Out of the total mass of products obtained, what is the percentage by mass of each product? A 32.4 % and 67.6 % B 38.3 % and 61.7 % C 42.3 % and 57.7 % D 50.0 % and 50.0 %

Accepted Answer

C

Question 21

21 Which diagram gives the skeletal formula of 2-chloropentan-3-ol? A B C D Cl Cl OH Cl Cl OH OH OH

Accepted Answer

A

Question 22

22 When 1-bromopropane is treated in succession with two reagents, X and Y, it produces propanoic acid. What are reagents X and Y? X Y A NaOH(aq) H+ / Cr2O7 2–(aq) B NaOH(aq) CO2 C KCN in ethanol HCl (aq) D KCN in ethanol NaOH(aq)

Accepted Answer

A

Question 23

23 Isomers X and Y both react with HBr. H3C Br Br Br C C C C H3C Br H3C CH3 X Y A mixture of X and Y is reacted with HBr. Which three structures represent three different possible products of this reaction? A (CH3)2CHCBr3 (CH3)2CBrCHBr2 CH3CHBrCHBrCH3 B (CH3)2CHCBr3 (CH3)2CBrCHBr2 CH3CBr2CHBrCH3 C (CH3)2CBrCBr3 (CH3)2CHCBr3 CH3CBr2CHBrCH3 D (CH3)2CBrCHBr2 CHBr2CBr(CH3)CH3 CH3CHBrCBr2CH3

Accepted Answer

B

Question 24

24 Oct-1-ene, CH3(CH2)5CH=CH2, is subjected to thermal cracking. Which combination of compounds W, X, Y and Z can be obtained? CH2=CH2 CH3CH=CH2 CH3CH2CH3 CH2=CHCH=CH2 W X Y Z A W, X, Y and Z B W, X and Y only C W, X and Z only D W and X only

Accepted Answer

A

Question 25

25 When phenacyl chloride, C6H5COCH2Cl, is reacted with aqueous NaOH, the substitution reaction follows an SN2 mechanism. Which structure represents a species formed during the reaction? A B H OH H δ+ δ– C6H5 C C + C6H5 C C Cl O H O– H C D – – H H H H δ– δ– δ– HO C Cl HO C Cl δ– C O C O C6H5 C6H5

Accepted Answer

C

Question 26

26 Complete combustion of compound X gives carbon dioxide and water only. A sample of X is mixed with aqueous potassium(V) dichromate and boiled under reflux for one hour. The mixture is then distilled and the only organic substance present is collected. The organic substance collected reacts with sodium to give hydrogen, but does not react with 2,4-dinitrophenylhydrazine reagent and does not react with ethanol in the presence of concentrated sulfuric acid to give an ester. What can be deduced from this information? A X is a carboxylic acid. B X is a ketone. C X is an alcohol. D X is an alkane.

Accepted Answer

C

Question 27

27 A compound Y has the following properties. • It is a liquid at room temperature and atmospheric pressure. • It does not mix completely with water. • It does not give steamy fumes with PCl5. What could Y be? A ethane B ethanoic acid C ethanol D ethyl ethanoate

Accepted Answer

D

Question 28

28 Coniine is the major constituent of the poison ‘oil of hemlock’. N CH2CH2CH3 H coniine Coniine can be synthesised by reacting ammonia with a dibromo compound, X. NH3 + C8H16Br2 → coniine + 2HBr X What is the name of compound X? A 1,1-dibromo-2-propylcyclopentane B 1,2-dibromo-2-propylcyclopentane C 1,4-dibromooctane D 1,5-dibromooctane

Accepted Answer

D

Question 29

29 A common industrial solvent is a mixture of propanone, CH3COCH3, and pentyl ethanoate CH3CO2(CH2)4CH3. Which reagent would have no reaction with this industrial solvent? A HCl (aq) B HCN(aq) with a little KCN C Na(s) D NaBH4

Accepted Answer

C

Question 30

30 An organic compound will decolorise dilute acidified aqueous potassium manganate(VII) on warming, but will not decolorise bromine water. What could the organic compound be? A butane B ethanol C ethene D ethanoic acid

Accepted Answer

B

Question 31

31 Which of the following molecules and ions have a regular trigonal planar shape? 1 BF3 2 CH3 + 3 Al Cl 3

Accepted Answer

A

Question 32

32 Ammonia and chlorine react in the gas phase. 8NH3 + 3Cl 2 → N2 + 6NH4Cl Which statements are correct? 1 Each nitrogen atom is oxidised. 2 Each chlorine atom is reduced. 3 Ammonia behaves as a base.

Accepted Answer

C

Question 33

33 Concentrated sulfuric acid behaves as a strong acid when it reacts with water. H2SO4(l) + aq → H+(aq) + HSO4 –(aq) The HSO4 – ion formed behaves as a weak acid. HSO4 –(aq) H+(aq) + SO4 2–(aq) Which statements are true for 1.0 mol dm–3 sulfuric acid? 1 [H+(aq)] is high 2 [SO4 2–(aq)] is high 3 [HSO4 –(aq)] = [SO4 2–(aq)]

Accepted Answer

D

Question 34

34 Silver chloride dissolves in aqueous ammonia. What happens in this process? 1 A co-ordinate bond is formed. 2 The oxidation number of nitrogen is unchanged. 3 Ammonia acts as a Brønsted-Lowry base.

Accepted Answer

B

Question 35

35 Compared with the HCl molecule, the bond ……X…… of the HBr molecule is ……Y…… Which pairs of words correctly complete the above sentence? X Y 1 energy less 2 polarity less 3 length greater

Accepted Answer

A

Question 36

36 Which statements are true about the Haber process for the manufacture of ammonia? 1 At higher temperatures, the yield goes down but the rate of production of ammonia is faster. 2 At higher pressures, the yield goes down but the rate of production of ammonia is faster. 3 In the presence of a catalyst, the yield goes down but the rate of production of ammonia is faster.

Accepted Answer

D

Question 37

37 Which compounds can be obtained from propene in a single reaction? 1 CH2OHCHOHCH3 2  (  CH2CH(CH3) ) n 3 CH2BrCH2CH2Br

Accepted Answer

B

Question 38

38 What are the same for a pair of optical isomers? 1 their empirical formula 2 their functional groups 3 their structural formula

Accepted Answer

A

Question 39

39 Which statements about the photochemical chlorination of ethane are correct? 1 Hydrogen gas is one of the products. 2 A propagation step in the mechanism is C2H6 + Cl • → C2H5• + HCl. 3 The initiation step is the homolytic fission of chlorine.

Accepted Answer

C

Question 40

40 The compound shown is a hormone produced during pregnancy to suppress ovulation. CH3 C O CH3 CH3 HO Which reagents would give positive results with this compound? 1 aqueous bromine 2 2,4-dinitrophenylhydrazine 3 Fehling’s reagent

Accepted Answer

B

Question paper16 pages

Mark scheme2 pages

Questions as text

Q1 · The molecular energy distribution curve represents the variation in energy of the…

Q2 · In which species are the numbers of protons, neutrons and electrons all different?

Q3 · What is the most likely shape of a molecule of hydrazine, N2H4?

Q4 · In which species does the underlined atom have an incomplete outer shell?

Q5 · Which solid contains more than one kind of bonding?

Q6 · Use of the Data Booklet is relevant to this question

Q7 · Two moles of compound P were placed in a vessel

Q8 · The value of the third ionisation energy of aluminium is 2740 kJ mol–1

Q9 · Methanol is manufactured by reacting carbon dioxide and hydrogen

Q10 · Which molecule has the largest overall dipole?

Q11 · In which substance does nitrogen exhibit the highest oxidation state?

Q12 · Red lead oxide, Pb3O4, is used in metal priming paints

Q13 · Which gas is present in the exhaust fumes of a car engine in a much greater amount than…

Q14 · Slaked lime, Ca(OH)2, may be made from limestone, CaCO3

Q15 · The period 4 elements gallium (Ga), germanium (Ge), arsenic (As) and selenium (Se) are…

Q16 · Chlorine shows oxidation states ranging from –1 to +7 in its compounds

Q17 · What can be seen when a piece of magnesium ribbon is placed in cold water?

Q18 · Use of the Data Booklet is relevant to this question

Q19 · Which substance does not produce a poisonous gas, when burnt in a limited amount of air?

Q20 · Use of the Data Booklet is relevant to this question

Q21 · Which diagram gives the skeletal formula of 2-chloropentan-3-ol?

Q22 · When 1-bromopropane is treated in succession with two reagents, X and Y, it produces…

Q23 · Isomers X and Y both react with HBr

Q24 · Oct-1-ene, CH3(CH2)5CH=CH2, is subjected to thermal cracking

Q25 · When phenacyl chloride, C6H5COCH2Cl, is reacted with aqueous NaOH, the substitution…

Q26 · Complete combustion of compound X gives carbon dioxide and water only

Q27 · A compound Y has the following properties

Q28 · Coniine is the major constituent of the poison ‘oil of hemlock’

Q29 · A common industrial solvent is a mixture of propanone, CH3COCH3, and pentyl ethanoate…

Q30 · An organic compound will decolorise dilute acidified aqueous potassium manganate(VII) on…

Q31 · Which of the following molecules and ions have a regular trigonal planar shape?

Q32 · Ammonia and chlorine react in the gas phase

Q33 · Concentrated sulfuric acid behaves as a strong acid when it reacts with water

Q34 · Silver chloride dissolves in aqueous ammonia

Q35 · Compared with the HCl molecule, the bond ……X…… of the HBr molecule is ……Y…… Which pairs…

Q36 · Which statements are true about the Haber process for the manufacture of ammonia?

Q37 · Which compounds can be obtained from propene in a single reaction?

Q38 · What are the same for a pair of optical isomers?

Q39 · Which statements about the photochemical chlorination of ethane are correct?

Q40 · The compound shown is a hormone produced during pregnancy to suppress ovulation

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