Cambridge A Level Chemistry 9701 — 2013 Oct/Nov Paper 1 · Variant 3

Question 1

1 Ammonium nitrate, NH4NO3, can decompose explosively when heated. NH4NO3  →  N2O  +  2H2O What are the changes in the oxidation numbers of the two nitrogen atoms in NH4NO3 when this reaction proceeds? A –2, –4 B +2, +6 C +4, –6 D +4, –4

Accepted Answer

D

Question 2

2 In the extraction of aluminium by electrolysis, why is it necessary to dissolve aluminium oxide in molten cryolite? A to reduce the very high melting point of the electrolyte B cryolite is a base; aluminium oxide is amphoteric C cryolite reacts with the aluminium oxide to form ions D molten aluminium oxide alone would not conduct electricity

Accepted Answer

A

Question 3

3 A 10 cm3 sample of 0.30 mol dm–3 Tl +NO3 – required 20 cm3 of 0.10 mol dm–3 acidified NH4VO3 to oxidise it to Tl 3+ in solution. Vanadium is the only element reduced in this reaction. What is the oxidation number of the vanadium in the reduced form? A +1 B +2 C +3 D +4

Accepted Answer

B

Question 4

4 Use of the Data Booklet is relevant to this question. Element X forms X– ions that can be oxidised to element X by acidified potassium manganate(VII). What could be the values of the first four ionisation energies of X? 1st 2nd 3rd 4th A 418 3070 4600 5860 B 577 1820 2740 11 600 C 590 1150 4940 6480 D 1010 1840 2040 4030

Accepted Answer

D

Question 5

5 Na2S2O3 reacts with dilute HCl to give a pale yellow precipitate. If 1 cm3 of 0.1 mol dm–3 HCl is added to 10 cm3 of 0.02 mol dm–3 Na2S2O3 the precipitate forms slowly. If the experiment is repeated with 1 cm3 of 0.1 mol dm–3 HCl and 10 cm3 of 0.05 mol dm–3 Na2S2O3 the precipitate forms more quickly. Why is this? A The activation energy of the reaction is lower when 0.05 mol dm–3 Na2S2O3 is used. B The collisions between reactant particles are more violent when 0.05 mol dm–3 Na2S2O3 is used. C The reactant particles collide more frequently when 0.05 mol dm–3 Na2S2O3 is used. D The reaction proceeds by a different pathway when 0.05 mol dm–3 Na2S2O3 is used.

Accepted Answer

C

Question 6

6 Which stage in the free radical substitution of ethane by chlorine will have the lowest activation energy? A Cl 2  →  2Cl ● B Cl ●  +  C2H6  →  C2H5●  +  HCl C C2H5●  +  Cl 2  →  C2H5Cl  +  Cl ● D Cl ●  +  C2H5●  →  C2H5Cl

Accepted Answer

D

Question 7

7 Measured values of the pressure, volume and temperature of a known mass of a gaseous compound are to be substituted into the equation pV = nRT. The measurements are used to calculate the relative molecular mass, Mr, of a compound. Which conditions of pressure and temperature would give the most accurate value of Mr? pressure temperature A high high B high low C low high D low low

Accepted Answer

C

Question 8

8 Which solid contains more than one kind of bonding? A copper B diamond C ice D magnesium oxide

Accepted Answer

C

Question 9

9 Use of the Data Booklet is relevant to this question. When an evacuated fluorescent light tube of volume 300 cm3 is filled with a gas at 300 K and 101 kPa, the mass of the tube increases by 1.02 g. The gas obeys the ideal gas equation pV = nRT. What is the identity of the gas? A argon B krypton C neon D nitrogen

Accepted Answer

B

Question 10

10 Nitrogen reacts with hydrogen to produce ammonia. N2(g)  +  3H2(g) 2NH3(g) A mixture of 1.00 mol of nitrogen, 3.00 mol of hydrogen and 1.98 mol of ammonia is allowed to reach equilibrium in a sealed vessel under certain conditions. It was found that 1.64 mol of nitrogen were present in the equilibrium mixture. What is the value of Kc under these conditions? A ( 0 . 70 ) 2 ( 1 . 64 )( 4 . 92 ) 3 B ( 1 . 34 ) 2 ( 1 . 64 )( 3 . 64 ) 3 C ( 1 . 64 )( 4 . 92 ) 3 ( 0 . 70 ) 2 D ( 1 . 64 )( 3 . 64 ) 3 ( 1 . 34 ) 2

Accepted Answer

A

Question 11

11 Use of the Data Booklet is relevant to this question. Which calcium compound contains 54.1 % by mass of calcium? A calcium hydroxide B calcium nitrate C calcium oxide D calcium sulfate

Accepted Answer

A

Question 12

12 Use of the Data Booklet is relevant to this question. The reaction between aluminium powder and anhydrous barium nitrate is used as the propellant in some fireworks. The reaction produces the metal oxides and nitrogen. 10Al  +  3Ba(NO3)2  →  5Al 2O3  +  3BaO  +  3N2 Which mass of barium oxide is produced when 5.40 g of aluminium powder reacts with an excess of anhydrous barium nitrate? A 1.62 g B 3.06 g C 9.18 g D 10.2 g

Accepted Answer

C

Question 13

13 The diagram shows some applications of compounds of Group II elements. used as a refractory lining in furnaces or kilns 1 4 calcium 2 used as a 5 magnesium carbonate building material oxide 3 6 used to manufacture an agricultural chemical to adjust soil pH Which numbered links are correct? calcium carbonate magnesium oxide A 1, 2 and 3 4 and 5 only B 1, 2 and 3 5 and 6 only C 2 and 3 only 4 only D 2 and 3 only 6 only

Accepted Answer

C

Question 14

14 River water in a chalky agricultural area may contain Ca2+, Mg2+, CO3 2–, HCO3 –, Cl − and NO3 – ions. In a water treatment plant, such water is treated by adding a calculated quantity of calcium hydroxide. What will be precipitated from the river water following the addition of calcium hydroxide? A CaCl 2 B CaCO3 C Ca(NO3)2 D Mg(NO3)2

Accepted Answer

B

Question 15

15 Ammonia exists as simple covalent molecules, NH3. Ammonia can react with suitable reagents to form products containing ammonium ions, NH4 +. Ammonia can also react with suitable reagents to form products containing amide ions, NH2 –. Which of these nitrogen-containing species are present in an aqueous solution of ammonia? A ammonia molecules, ammonium ions and amide ions B ammonia molecules and ammonium ions only C ammonia molecules only D ammonium ions only

Accepted Answer

B

Question 16

16 Carbon, nitrogen and sulfur are non-metals. Which statement about their oxides, XO2, is correct? (Where X represents carbon, nitrogen or sulfur.) A All of the XO2 molecules are linear. B In XO2, each element has its highest oxidation number. C All XO2 molecules dissolve in water to form dibasic acids. D All XO2 molecules are formed as a result of burning petrol in a car engine.

Accepted Answer

D

Question 17

17 Which oxide is insoluble in aqueous sodium hydroxide? A MgO B Al 2O3 C P4O10 D SO2

Accepted Answer

A

Question 18

18 The graph below shows the variation of the first ionisation energy with the number of protons for some elements. Q Y first ionisation X energy / kJ mol–1 V W S U T R proton number Which statement is correct? A Elements Q and Y are in the same period in the Periodic Table. B The general increase from elements R to Y is due to increasing atomic radius. C The small decrease between elements S and T is due to decreased shielding. D The small decrease between elements V and W is due to repulsion between paired electrons.

Accepted Answer

D

Question 19

19 Use of the Data Booklet is relevant to this question. Elements J and K react together to form compound L. Elements J and K are both in Period 3. Element J has the smallest atomic radius in Period 3. There are only two elements in Period 3 which have a lower melting point than element K. Which compound could be L? A MgCl 2 B MgS C Na2S D PCl 3

Accepted Answer

D

Question 20

20 Which diagram gives the skeletal formula of 2-bromopentan-4-ol? A B C D OH Br Br Br OH OH Br OH

Accepted Answer

A

Question 21

21 Including structural and stereoisomers, how many isomers are there of C2H2Br2? A 2 B 3 C 4 D 5

Accepted Answer

B

Question 22

22 Which reaction will give the best yield of 2-chloropropane? A chlorine gas with propane gas in the presence of uv light B chlorine gas with propene gas in the dark C propan-2-ol with dilute NaCl (aq) D propan-2-ol with PCl 5

Accepted Answer

D

Question 23

23 Pent-2-ene, CH3CH2CH=CHCH3, reacts in a similar way to ethene. Pent-2-ene is reacted with cold, dilute, acidified manganate(VII) ions. What will be produced in the greatest amount? A CH3CH2CH(OH)CH(OH)CH3 B CH3CH2COCOCH3 C a mixture of CH3CH2CH(OH)CH2CH3  and  CH3CH2CH2CH(OH)CH3 D CH3CH2COOH  and  CH3COOH

Accepted Answer

A

Question 24

24 Including structural and stereoisomers, how many isomeric products are produced when alcoholic KOH reacts with 2-chlorobutane? A 1 B 2 C 3 D 4

Accepted Answer

C

Question 25

25 Chlorofluorocarbons, CFCs, can be used as refrigerants, aerosol propellants and fire extinguishers. CFCs such as CCl 3F and CCl 2F2 are more stable than chloroalkanes such as CCl 4. What is the reason for their greater stability? A Fluorine has a higher first ionisation energy than chlorine. B Fluorine radicals are more stable than chlorine radicals. C The C–F bond energy is larger than the C–Cl bond energy. D The C–F bond is more polar than the C–Cl bond.

Accepted Answer

C

Question 26

26 Halogenoalkanes react with aqueous NaOH to give alcohols. The mechanism involved is either SN1 or SN2. Which halogenoalkane produces the highest percentage of product by an SN1 mechanism, when treated with aqueous NaOH? A 2-bromopropane B 2-chloropropane C 1-iodo-2-methylpropane D 2-iodo-2-methylpropane

Accepted Answer

D

Question 27

27 An alcohol with molecular formula CnH2n+1OH has a chiral carbon atom but does not react with hot, acidified K2Cr2O7. What is the smallest possible value for n ? A 5 B 6 C 7 D 8

Accepted Answer

C

Question 28

28 Compound X reacts with ethanoic acid in the presence of an H+ catalyst to produce the compound below. O H H O H3C C C C O C CH3 H H What is the molecular formula of compound X? A C2H6O2 B C2H6O3 C C4H8O D C4H8O2

Accepted Answer

D

Question 29

29 How many hydrogen atoms are added to each molecule of ethanal when it is reacted with NaBH4 in water? A 1 B 2 C 4 D 6

Accepted Answer

B

Question 30

30 Which fragment could appear in the chain produced by polymerising 1,1-dichloroethene? A – CH2 – CH2 – CCl 2 – CCl 2 – CH2 – CH2 – B – CHCl – CHCl – CHCl – CHCl – CHCl – CHCl – C – CH2 – CCl 2 – CH2 – CH2 – CH2 – CCl 2 – D – CCl 2 – CCl 2 – CH2 – CH2 – CH2 – CCl 2 –

Accepted Answer

A

Question 31

31 The 1H3 + ion was first characterised by J. J. Thomson over a century ago. 6Li is a rare isotope of lithium which forms the 6Li+ ion. Which statements are correct? 1 Both ions contain the same number of protons. 2 Both ions contain the same number of electrons. 3 Both ions contain the same number of neutrons.

Accepted Answer

B

Question 32

32 The diagram represents the Boltzmann distribution of molecular energies at a given temperature. number of molecules energy Which of the factors that affect the rate of a reaction can be explained using such a Boltzmann distribution? 1 increasing the concentration of reactants 2 increasing the temperature 3 the addition of a catalyst

Accepted Answer

C

Question 33

33 Methanoic acid molecules, HCO2H, and hydrogen carbonate ions, HCO3 –, can both behave as acids. Why does a solution of methanoic acid have a lower pH than a solution of sodium hydrogen carbonate of the same concentration? 1 HCO2H molecules dissociate more fully than HCO3 – ions do. 2 Each HCO2H molecule has two hydrogen atoms; each HCO3 – ion only has one. 3 Methanoic acid is a weaker acid than sodium hydrogen carbonate.

Accepted Answer

D

Question 34

34 The following equilibrium is an exothermic reaction in the forward direction. 2CrO4 2–(aq)  +  2H+(aq) Cr2O7 2–(aq)  +  H2O(l) What happens when the concentration of CrO4 2– ions increases and the temperature decreases? 1 The concentration of Cr2O7 2– ions increases. 2 The equilibrium constant increases. 3 The activation energy decreases.

Accepted Answer

B

Question 35

35 Which processes involve the conversion of sulfur dioxide into sulfur trioxide? 1 the combustion of sulfur contaminated fossil fuels 2 the Contact process for manufacturing sulfuric acid 3 the catalytic oxidation of sulfur dioxide by oxides of nitrogen

Accepted Answer

C

Question 36

36 Which chlorides of Period 3 elements will form a neutral solution when added to water? 1 NaCl 2 Al 2Cl 6 3 PCl 5

Accepted Answer

D

Question 37

37 A series of tests was carried out on the compound shown below. O O CH3CCH2CH CHCH2C H Which pairs of reagents would both give a positive result for this compound? 1 Tollens’ reagent and a solution containing acidified dichromate(VI) ions 2 aqueous bromine and Fehling’s reagent 3 2,4-dinitrophenylhydrazine reagent and sodium carbonate

Accepted Answer

B

Question 38

38 The reaction of ethanal, CH3CHO, with HCN to form a cyanohydrin is catalysed by NaCN. What are features of the intermediate of this reaction? 1 It is chiral. 2 It has a single negative charge on one of its atoms. 3 It is a nucleophile.

Accepted Answer

A

Question 39

39 The ester C2H5CO2CH2CH2CH3 can be made in a school or college laboratory by a sequence of reactions using compound X as the only organic material. What might be the identity of compound X? 1 CH3CH2CH2OH 2 CH3CH2CHO 3 CH3COCH3

Accepted Answer

B

Question 40

40 The structural formulae of two compounds are shown below. O O CH3CH2CH2CH2CH2C CH3CH2CH2CH2CH2OC OH H Which statements about these compounds are correct? 1 The two compounds are structural isomers of each other. 2 The empirical formula of both compounds is C3H6O. 3 Both compounds are carboxylic acids.

Accepted Answer

B

Question paper12 pages

Mark scheme2 pages

Questions as text

Q1 · Ammonium nitrate, NH4NO3, can decompose explosively when heated

Q2 · In the extraction of aluminium by electrolysis, why is it necessary to dissolve aluminium…

Q3 · A 10 cm3 sample of 0.30 mol dm–3 Tl +NO3 – required 20 cm3 of 0.10 mol dm–3 acidified…

Q4 · Use of the Data Booklet is relevant to this question

Q5 · Na2S2O3 reacts with dilute HCl to give a pale yellow precipitate

Q6 · Which stage in the free radical substitution of ethane by chlorine will have the lowest…

Q7 · Measured values of the pressure, volume and temperature of a known mass of a gaseous…

Q8 · Which solid contains more than one kind of bonding?

Q9 · Use of the Data Booklet is relevant to this question

Q10 · Nitrogen reacts with hydrogen to produce ammonia

Q11 · Use of the Data Booklet is relevant to this question

Q12 · Use of the Data Booklet is relevant to this question

Q13 · The diagram shows some applications of compounds of Group II elements

Q14 · River water in a chalky agricultural area may contain Ca2+, Mg2+, CO3 2–, HCO3 –, Cl −…

Q15 · Ammonia exists as simple covalent molecules, NH3

Q16 · Carbon, nitrogen and sulfur are non-metals

Q17 · Which oxide is insoluble in aqueous sodium hydroxide?

Q18 · The graph below shows the variation of the first ionisation energy with the number of…

Q19 · Use of the Data Booklet is relevant to this question

Q20 · Which diagram gives the skeletal formula of 2-bromopentan-4-ol?

Q21 · Including structural and stereoisomers, how many isomers are there of C2H2Br2?

Q22 · Which reaction will give the best yield of 2-chloropropane?

Q23 · Pent-2-ene, CH3CH2CH=CHCH3, reacts in a similar way to ethene

Q24 · Including structural and stereoisomers, how many isomeric products are produced when…

Q25 · Chlorofluorocarbons, CFCs, can be used as refrigerants, aerosol propellants and fire…

Q26 · Halogenoalkanes react with aqueous NaOH to give alcohols

Q27 · An alcohol with molecular formula CnH2n+1OH has a chiral carbon atom but does not react…

Q28 · Compound X reacts with ethanoic acid in the presence of an H+ catalyst to produce the…

Q29 · How many hydrogen atoms are added to each molecule of ethanal when it is reacted with…

Q30 · Which fragment could appear in the chain produced by polymerising 1,1-dichloroethene?

Q31 · The 1H3 + ion was first characterised by J

Q32 · The diagram represents the Boltzmann distribution of molecular energies at a given…

Q33 · Methanoic acid molecules, HCO2H, and hydrogen carbonate ions, HCO3 –, can both behave as…

Q34 · The following equilibrium is an exothermic reaction in the forward direction

Q35 · Which processes involve the conversion of sulfur dioxide into sulfur trioxide?

Q36 · Which chlorides of Period 3 elements will form a neutral solution when added to water?

Q37 · A series of tests was carried out on the compound shown below

Q38 · The reaction of ethanal, CH3CHO, with HCN to form a cyanohydrin is catalysed by NaCN

Q39 · The ester C2H5CO2CH2CH2CH3 can be made in a school or college laboratory by a sequence of…

Q40 · The structural formulae of two compounds are shown below

What was in this paper

What you needed in this session

Other variants, same session

This paper, other years