Cambridge A Level Chemistry 9701 — 2006 Oct/Nov Paper 1 · Variant 1

1 The amount of calcium ions in a sample of natural water can be determined by using an ion- exchange column as shown in the diagram. water sample ion-exchange resin A 50 cm3 sample of water containing dissolved calcium sulphate was passed through the ion- exchange resin. Each calcium ion in the sample was exchanged for two hydrogen ions. The resulting acidic solution collected in the flask required 25 cm3 of 1.0 × 10–2 mol dm–3 potassium hydroxide for complete neutralisation. What was the concentration of the calcium sulphate in the original sample? A 2.5 × 10–3 mol dm–3 B 1.0 × 10–2 mol dm–3 C 2.0 × 10–2 mol dm–3 D 4.0 × 10–2 mol dm–3

Mark scheme: A

More questions on Reacting masses and volumes (of solutions and gases)

2 Three successive elements in the Periodic Table have first ionisation energies which have the pattern shown in the diagram. x x first ionisation energy x atomic number What could be the first element of this sequence? A C B N C F D Na

Mark scheme: C

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3 Use of the Data Booklet is relevant to this question. The electronic structures of calcium, krypton, phosphorus and an element X are shown. Which electronic structure is that of element X? A 1s22s22p63s23p3 B 1s22s22p63s23p64s2 C 1s22s22p63s23p63d64s2 D 1s22s22p63s23p63d104s24p6

Mark scheme: C

More questions on Electrons, energy levels and atomic orbitals

4 Samples of 10 cm3 of each of the first four members of the alkane series are separately mixed with 70 cm3 of oxygen. Each is then burned and the total volume, V, of residual gas measured again at room temperature and pressure. Which graph represents the results that would be obtained? A B V / cm3 V / cm3 X 80 80 X 60 60 X 40 X 40 X X 20 X 20 X 0 0 CH4 C3H8 CH4 C3H8 C2H6 C4H10 C2H6 C4H10 C D V / cm3 V / cm3 80 80 60 60 X X X X X 40 X 40 X 20 X 20 0 0 CH4 C3H8 CH4 C3H8 C2H6 C4H10 C2H6 C4H10

Mark scheme: D

More questions on Reacting masses and volumes (of solutions and gases)

5 Which diagram describes the formation of a π bond from the overlap of its orbitals? A B C D

Mark scheme: B

More questions on Shapes of organic molecules; σ and π bonds

6 For an ideal gas, the plot of pV against p is a straight line. For a real gas, such a plot shows a deviation from ideal behaviour. The plots of pV against p for three real gases are shown below. The gases represented are ammonia, hydrogen and nitrogen. X Y Z pV ideal gas 0 0 p What are the identities of the gases X, Y and Z? X Y Z A ammonia nitrogen hydrogen B hydrogen nitrogen ammonia C nitrogen ammonia hydrogen D nitrogen hydrogen ammonia

Mark scheme: D

More questions on The gaseous state: ideal and real gases and pV = nRT

7 Magnesium oxide may be used for the lining of an electric furnace for making crockery. Which properties of magnesium oxide help to explain this use? strong forces ionic electrical between particles bonding conductor A yes yes no B yes no yes C no yes no D no no yes

Mark scheme: A

More questions on Bonding and structure

8 For which equation is the enthalpy change correctly described as an enthalpy change of formation? A 2NO(g) → N2(g) + O2(g) B 2CO(g) + O2(g) → 2CO2(g) C H2O(l) + NaCl(s) → NaCl(aq) D K(s) + Mn(s) + 2O2(g) → KMnO4(s)

Mark scheme: D

More questions on Enthalpy change, ΔH

9 Given CO(g) + 2 1 O2(g) → CO2(g) ∆Ho = –283 kJ mol–1 H2(g) + 2 1 O2(g) → H2O(l) ∆Ho = –286 kJ mol–1 H2O(g) → H2O(l) ∆Ho = –44 kJ mol–1 what is the change in enthalpy, ∆Ho, for the following reaction? CO2(g) + H2(g) → CO(g) + H2O(g) A –525 kJ mol–1 B –41 kJ mol–1 C +41 kJ mol–1 D +525 kJ mol–1

Mark scheme: C

More questions on Hess’s law

10 In some early paintings, lead(II) carbonate was used as a white pigment. In the 19th century hydrogen sulphide from burning coal reacted with this pigment to form black lead(II) sulphide, PbS. The original colour of the painting may be restored by carefully treating the area with dilute hydrogen peroxide, producing lead(II) sulphate which is also white. What is the role of the hydrogen peroxide? A catalyst B oxidising agent C reducing agent D solvent

Mark scheme: B

More questions on Redox processes: electron transfer and changes in oxidation number (oxidation state)

11 The equilibrium constant, Kc, for the reaction to form ethyl ethanoate from ethanol and ethanoic acid, C2H5OH + CH3CO2H CH3CO2C2H5 + H2O, at 60 oC is 4.00. When 1.00 mol each of ethanol and ethanoic acid are allowed to reach equilibrium at 60 oC, what is the number of moles of ethyl ethanoate formed? A 1 B 2 C 1 D 3 3 3 4 4

Mark scheme: B

More questions on Chemical equilibria: reversible reactions, dynamic equilibrium

12 The diagram shows the Maxwell-Boltzmann energy distribution curves for molecules of a sample of a gas at two different temperatures. Which letter on the axes represents the most probable energy of the molecules at the lower temperature? A B C D

Mark scheme: C

More questions on Effect of temperature on reaction rates and the concept of activation energy

13 Steam is passed over heated magnesium to give compound X and hydrogen. What is not a property of compound X? A It has a high melting point. B It is a basic oxide. C It is a white solid. D It is very soluble in water.

Mark scheme: D

More questions on Periodicity of chemical properties of the elements in Period 3

14 A 5.00 g sample of an anhydrous Group II metal nitrate loses 3.29 g in mass on strong heating. Which metal is present? A magnesium B calcium C strontium D barium

Mark scheme: B

More questions on Similarities and trends in the properties of the Group 2 metals, magnesium to barium, and their compounds

15 Which of the following is not a correct statement about iodine? A A crystal of iodine contains covalent bonds and van der Waals’ forces. B Iodine vapour is purple. C The first ionisation energy of iodine is less than that of bromine. D The hydride of iodine is of greater thermal stability than that of bromine.

Mark scheme: D

More questions on Physical properties of the Group 17 elements

16 Mixing aqueous silver nitrate and aqueous sodium chloride produces a precipitate. Addition of which reagent to the mixture gives a colourless solution? A aqueous ammonia B aqueous potassium iodide C dilute hydrochloric acid D dilute nitric acid

Mark scheme: A

More questions on Some reactions of the halide ions

17 Which is the complete list of all the products from the reaction of concentrated sulphuric acid with potassium bromide? A potassium hydrogensulphate and hydrogen bromide B potassium hydrogensulphate, hydrogen bromide and bromine C potassium hydrogensulphate, hydrogen bromide, bromine and water D potassium hydrogensulphate, hydrogen bromide, bromine, water and sulphur dioxide

Mark scheme: D

More questions on The chemical properties of the halogen elements and the hydrogen halides

18 Sulphur dioxide is an important food preservative. Which property makes sulphur dioxide useful in this role? A It is a gas. B It is a reducing agent. C It reacts with oxygen to form sulphur trioxide. D It reacts with water to form an acidic solution.

Mark scheme: B

More questions on Nitrogen and sulfur

19 In the Contact process for the production of sulphuric acid, sulphur dioxide is mixed with air and passed over a vanadium(V) oxide catalyst at about 450 oC and a pressure slightly above atmospheric pressure. 2SO2 + O2 2SO3 ; ∆H negative What affects the choice of conditions for this reaction? A A lower temperature would not raise the concentration of SO3 at equilibrium. B At a lower temperature of 300 oC the V2O5 catalyst would not be effective. C At 450 oC nitrogen and oxygen from the air combine to form nitrogen oxides which are needed as additional catalysts. D The heat generated by the reaction raises the temperature of the catalyst bed to 600 oC at which temperature the reaction begins to take place.

Mark scheme: B

More questions on Homogeneous and heterogeneous catalysts

20 In which class of compound, in its general formula, is the ratio of hydrogen atoms to carbon atoms the highest? A alcohols B aldehydes C carboxylic acids D halogenoalkanes

Mark scheme: A

More questions on Formulas, functional groups and the naming of organic compounds

21 What is the total number of different chloroethanes, formula C2H6-nCln, where n can be any integer from 1 to 4? A 4 B 6 C 7 D 8

Mark scheme: C

More questions on Isomerism: structural isomerism and stereoisomerism

22 Which reaction is an example of nucleophilic substitution? A CH3CH2Br → CH2=CH2 + HBr B CH2=CH2 + HBr → CH3CH2Br C C3H7Br + H2O → C3H7OH + HBr D C2H6 + Br2 → C2H5Br + HBr

Mark scheme: C

More questions on Halogenoalkanes

23 Which alkene could exist in cis and trans forms? A CH3CH2CH2CH CH2 B CH3CH2CH CHCH3 C CH3CH2C CH2 CH3 D CH3CH CCH3 CH3

Mark scheme: B

More questions on Isomerism: structural isomerism and stereoisomerism

24 When gaseous chemicals are transported by road or by rail they are classified as follows. flammable non-flammable poisonous Which gas is non-flammable? A butane B hydrogen C oxygen D propene

Mark scheme: C

More questions on Alkanes

25 Which equation or statement describes what happens when poly(propene) is burned in an excess of air? A (C3H6)n + 1 2 1 nO2 → 3nC + 3nH2O B (C3H6)n + 4 2 1 nO2 → 3nCO2 + 3nH2O C (C3H6)n + 6nO2 → 3nCO2 + 3nH2O D Poly(propene) does not burn.

Mark scheme: B

More questions on Addition polymerisation

26 When (chloromethyl)benzene, C6H5CH2Cl, is treated in succession with two reagents X and Y, it gives phenylethanoic acid, C6H5CH2CO2H. What are reagents X and Y? X Y A NaOH(aq) K2Cr2O7(aq) B Cl2(aq) NaOH(aq) C NaCN (in aqueous ethanol) dilute H2SO4 D NaOH(aq) CO2

Mark scheme: C

More questions on Organic synthesis

27 Which compound • is unaffected by hot alkaline potassium manganate(VII); • gives hydrogen when treated with sodium? A (CH3)2CHCOCH3 B (CH3)3COH C CH3CH2CH(OH)CH3 D CH3CO2CH(CH3)2

Mark scheme: B

More questions on Alcohols

28 A common industrial solvent is a mixture of propanone, CH3COCH3, and pentyl ethanoate CH3CO2(CH2)4CH3. Which reagent would have no effect on this solvent? A Na(s) B NaBH4 C NaOH(aq) D 2,4-dinitrophenylhydrazine reagent

Mark scheme: A

More questions on Aldehydes and ketones

29 Apples, the fruit of trees of the genus Malus, are rich in malic acid. Malic acid may be synthesised in the laboratory in two steps. step 1 step 2 NCCH2CHO X HO2CCH2CH(OH)CO2H malic acid Which reagents could be used for this synthesis? step 1 step 2 A HCl (aq) HCN(g) B HCN, NaCN(aq/alcoholic) H2SO4(aq) C H2SO4(aq) K2Cr2O7 / H2SO4(aq) D KCN(aq/alcoholic) HCl (aq)

Mark scheme: B

More questions on Nitriles and hydroxynitriles

30 Which pair of compounds is formed when the ester C2H5CO2CH3 is boiled with aqueous sodium hydroxide? A C2H5CO2H CH3OH B C2H5CO2Na CH3ONa C C2H5CO2Na CH3OH D C2H5OH CH3CO2Na

Mark scheme: C

More questions on Esters

31 The chlorine oxide free radical, ClO•, is formed during the depletion of the ozone layer by chlorofluoroalkanes (CFCs). Cl • + O3 → ClO• + O2 Which features are present in the chlorine oxide free radical? 1 an odd number of electrons 2 a single covalent bond 3 a dative covalent bond from oxygen to chlorine

Mark scheme: B

More questions on Particles in the atom and atomic radius

32 Concentrated sulphuric acid behaves as a strong acid when it reacts with water. H2SO4(l) + aq → H+(aq) + HSO (aq) − 4 The HSO ion formed behaves as a weak acid. − 4 HSO (aq) − H+(aq) + SO 2 − (aq) 4 4 Which statements are true for 1.0 mol dm–3 sulphuric acid? 1 [H+(aq)] is high 2 [ SO 2 − (aq)] is high 4 3 [ HSO (aq)] = [ − SO 2 − (aq)] 4 4

Mark scheme: D

More questions on Acids and bases

33 A reversible reaction is catalysed. Which statements about the effects of the catalyst on this system are correct? 1 The catalyst alters the mechanism of the reaction. 2 The catalyst reduces the energy of activation (the energy barrier) for both the forward and the backward reaction. 3 The catalyst alters the composition of the equilibrium mixture.

Mark scheme: B

More questions on Homogeneous and heterogeneous catalysts

34 Which magnesium compounds lose mass when heated by a Bunsen flame? 1 magnesium carbonate 2 magnesium nitrate 3 magnesium oxide

Mark scheme: B

More questions on Similarities and trends in the properties of the Group 2 metals, magnesium to barium, and their compounds

35 What happens when chlorine is bubbled through aqueous sodium hydroxide solution? 1 In cold solution, ClO–(aq) ions are formed. 2 In hot solution, ClO3 –(aq) ions are formed. 3 Disproportionation of chlorine occurs in both cold and hot aqueous solutions.

Mark scheme: A

More questions on The reactions of chlorine

36 Which fertilisers, when washed out of soil by rain, cause excessive growth of river plants and algae with the result that fish in the river die? 1 K2SO4 2 NH4NO3 3 NaNO3

Mark scheme: C

More questions on Nitrogen and sulfur

37 The following three hydrocarbons all occur naturally. Which of these will be split into two organic compounds, both containing a ketone group, when treated with hot acidified potassium manganate(VII)? 1 2 3

Mark scheme: D

More questions on Alkenes

38 Which are properties of fluoroalkanes? 1 They are less reactive than the corresponding chloroalkanes. 2 They are non-flammable. 3 The C-F bond is stronger than a C-Cl bond.

Mark scheme: A

More questions on Halogen compounds

39 Which compounds are able to react with concentrated sulphuric acid to give a product that will decolourise acidic potassium manganate(VII)? 1 (CH3)3COH 2 CH3CH2CH(OH)CH3 3 CH3CO2H

Mark scheme: B

More questions on Alcohols

40 Rofecoxib, an efficient drug against arthritis, has the following structure. R is an inert group. R CH2 C O * C C O Which reactions are possible with this structure? 1 The bond marked is hydrolysed by heating with aqueous sodium hydroxide. 2 Aqueous bromine is decolourised. 3 An orange precipitate is formed with 2,4-dinitrophenylhydrazine reagent.

Mark scheme: B

More questions on Aldehydes and ketones