Cambridge A Level Chemistry 9701 — 2003 Oct/Nov Paper 1 · Variant 1

This document consists of 14 printed pages and 2 blank pages. SP (NF/KN) S34065/4 © UCLES 2003 [Turn over CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certificate of Education Advanced Subsidiary Level and Advanced Level CHEMISTRY 9701/01 Paper 1 Multiple Choice October/November 2003 1 hour Additional Materials: Data Booklet Multiple Choice Answer Sheet Soft clean eraser Soft pencil (type B or HB is recommended) READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, Centre number and candidate number on the answer sheet in the spaces provided unless this has been done for you. There are forty questions on this paper. Answer all questions. For each question there are four possible answers A, B, C, and D. Choose the one you consider correct and record your choice in soft pencil on the separate answer sheet. Read the instructions on the Answer Sheet very carefully. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet.

2 9701/1/O/N/03 Section A For each question there are four possible answers, A, B, C, and D. Choose the one you consider to be correct. 1 Use of the Data Booklet is relevant to this question. Analytical chemists can detect very small amounts of amino acids, down to 3 × 10–21mol. How many molecules of an amino acid (Mr = 200) would this be? A 9 B 200 C 1800 D 360 000 2 Use of the Data Booklet is relevant to this question. A garden fertiliser is said to have a phosphorus content of 30.0% ‘P2O5 soluble in water’. What is the percentage by mass of phosphorus in the fertiliser? A 6.55% B 13.1 % C 26.2% D 30.0% 3 A sample of the hydrocarbon C6H12 is completely burned in dry oxygen and the product gases are collected as shown. [Ar : H, 1 ; C, 12 ; O, 16.] The increases in mass of the collecting vessels P and Q of the apparatus are MP and MQ, respectively. What is the ratio MP / MQ? A 0.41 B 0.82 C 1.2 D 2.4 H2O + CO2 + excess of O2 excess of O2 sodalime (to absorb CO2) anhydrous calcium chloride (to absorb H2O) Q P

3 9701/1/O/N/03 [Turn over 4 Unnilpentium is an artificial element. One of its isotopes is 262 105Unp. Which of the following statements is correct? A 262 105Unp has a nucleon number of 105. B The atom 260 105X is an isotope of 262 105Unp. C There are 262 neutrons in 262 105Unp. D The proton number of 262 105Unp is 262. 5 The table gives the successive ionisation energies for an element X. What could be the formula of the chloride of X? A XCl B XCl2 C XCl3 D XCl4 6 Which molecule contains only six bonding electrons? A C2H4 B C2F6 C H2O D NF3 7 Chemists have been interested in the properties of hydrogen selenide, H2Se, to compare it with ‘bad egg’ gas hydrogen sulphide, H2S. Which set of data would the hydrogen selenide molecule be expected to have? 1st 2nd 3rd 4th 5th 6th ionisation energy / kJ mol–1 950 1800 2700 4800 6000 12300 number of lone pairs bond angle on Se atom A 1 104° B 2 104° C 2 109° D 2 180°

4 9701/1/O/N/03 8 A substance commonly found in the house or garden has the following properties. • It is combustible. • It is an electrical insulator. • It melts over a range of temperature. What could the substance be? A brass B paper C poly(ethene) D silicon(IV) oxide 9 Use of the Data Booklet is relevant to this question. In an experiment using a gas syringe, 0.10 g of a gas is found to occupy 83.1 cm3, measured at standard pressure (1.0 × 105 Pa) and 27°C. What is the relative molecular mass of the gas? A B C D 0.10 × 8.31 × 300 1.0 × 105 × 83.1 × 10–6 0.10 × 8.31 × 27 1.0 × 105 × 83.1 × 10–6 0.10 × 8.31 × 300 1.0 × 105 × 83.1 0.10 × 8.31 × 27 1.0 × 105 × 83.1

5 9701/1/O/N/03 [Turn over 10 The value of pV is plotted against p for two gases, an ideal gas and a non-ideal gas, where p is the pressure and V is the volume of the gas. Which of the following gases shows the greatest deviation from ideality? A ammonia B ethene C methane D nitrogen 11 The ‘flash’ produced by nineteenth century photographers to take indoor photographs was obtained from the following reaction. 3Mg + KClO3 →3MgO + KCl The standard enthalpy changes of formation are given below. What is the standard enthalpy change of the ‘flash’ reaction? A –3(–602) + (–437) – (–391) B (–602) + (–437) – (–391) C 3(–602) + (–437) – (–391) D (–602) + 3(–437) – 3(–391) pV 0 non-ideal gas 0 p ideal gas ∆H o_ f / kJmol–1 MgO –602 KCl –437 KClO3 –391

6 9701/1/O/N/03 12 Why does the exothermic reaction C(diamond) →C(graphite) ∆H = –3 kJ mol–1 not occur spontaneously? A A tetrahedral configuration is always more stable than a planar one. B Diamond has only strong covalent bonds whereas graphite has both covalent bonds and van der Waals’ forces. C The change from diamond to graphite has a high activation energy. D The density of graphite is less than that of diamond. 13 The sketch below shows the variation of first ionisation energy with proton number for six elements of consecutive proton numbers between 1 and 18 (H to Ar). What is the identity of the element X? A Mg B Al C Si D P 14 The metals of Group II react readily with oxygen to form compounds of general formula MO. When each of these oxides is added to water, which forms the most alkaline solution? A MgO B CaO C SrO D BaO 15 One mole of each of the following compounds is strongly heated and any gas produced is collected at room temperature and pressure. From which compound is 24dm3 of gas likely to be collected? [One mole of any gas occupies 24dm3 at room temperature and pressure.] A MgCl2 B MgCO3 C Mg(NO3)2 D Mg(OH)2 X proton number ionisation energy

7 9701/1/O/N/03 [Turn over 16 In black and white photographic film, light converts silver chloride into metallic silver. After the film has been developed, the unexposed silver chloride is removed by reaction with sodium thiosulphate to produce a ‘fixed’ negative. AgCl + 2Na2S2O3 →4Na+ + Cl – + [Ag(S2O3)2]3– What is the function of thiosulphate? A to make the silver ions soluble B to oxidise the silver ions C to oxidise the silver metal D to reduce silver ions 17 In what order does the reducing power of the hydrogen halides increase? A HCl, HBr, HI B HCl, HI, HBr C HBr, HI, HCl D HI, HBr, HCl 18 In a solution of ammonia in water, what combination of ionic and molecular forms of ammonia are present? A ions only B ions and simple molecules only C simple molecules and hydrogen-bonded molecules only D simple molecules, hydrogen–bonded molecules and ions 19 Nitrogen is frequently used as an inert atmosphere because it is an unreactive gas. Which is the best explanation of this unreactivity? A Its molecule contains a triple bond. B The bond energy of the molecule is high (994 kJ mol–1). C The bond in its molecule is very short (0.110 nm). D The three p orbitals of nitrogen are half-filled. 20 How many alcohols (including both structural isomers and stereoisomers) can have the molecular formula C4H10O? A 3 B 4 C 5 D 6

8 9701/1/O/N/03 21 Hydrogen bromide reacts with ethene to form bromoethane. What is the best description of the organic intermediate in this reaction? A It contains carbon, hydrogen and bromine. B It has a negative charge. C It is an electrophile. D It is a free radical. 22 On strong heating a hydrocarbon produces ethene, propane and but-1-ene in the mole ratio 5 : 1 : 1. What is the molecular formula of the hydrocarbon? A C17H34 B C17H36 C C19H38 D C19H40 23 1,2-Dibromo-3-chloropropane (DBCP) has been used in the control of earthworms in agricultural land. What would be the best synthesis of this compound? A CH3CH2CH2Cl + 2Br2 →DBCP + 2HBr B CH3CHBrCH2Br + Cl2 →DBCP + HCl C CH2=CHCH2Cl + Br2 →DBCP D ClCH2CH=CH2 + PBr5 →DBCP + PBr3 24 Each of the following compounds is effective as a refrigerant. The release of which one of these causes the greatest depletion of the ozone layer? A CCl2F2 B CH3OCH3 C CH3CHF2 D CH3CH2CH3 25 1,1-Dichloropropane reacts with aqueous sodium hydroxide in a series of steps to give propanal. NaOH(aq) CH3CH2CHCl2 →CH3CH2CHO What is the mechanism of the first step of this reaction? A electrophilic substitution B elimination C nucleophilic substitution D oxidation

9 9701/1/O/N/03 [Turn over 26 Which alcohol gives only one oxidation product when warmed with dilute acidified potassium dichromate(VI)? A butan-1-ol B butan-2-ol C 2-methylpropan-1-ol D 2-methylpropan-2-ol 27 What will react differently with the two isomeric pentanols, (CH3)3CCH2OH and (CH3)2CHCH2CH2OH? A acidified aqueous potassium manganate(VII) B concentrated sulphuric acid C phosphorus pentachloride D sodium 28 How many hydrogen atoms in a molecule of glycerol, HOCH2CH(OH)CH2OH, may be substituted by deuterium on dissolving it in an excess of D2O? A 2 B 3 C 5 D 8 29 CH3CH2COCH2CH3 reacts with hydrogen cyanide to form a cyanohydrin. Which features apply to the product? A It has one chiral centre. B It is formed by electrophilic addition. C It is formed via a C–OH intermediate. D Its formation requires the use of cyanide ions as a catalyst.

10 9701/1/O/N/03 30 A compound X has all of the properties below. • It is a liquid at 25°C. • It mixes completely with water. • It reacts with aqueous sodium hydroxide. What could X be? A ethanoic acid B ethanol C ethene D ethyl ethanoate

11 9701/1/O/N/03 [Turn over Section B For each of the questions in this section, one or more of the three numbered statements 1 to 3 may be correct. Decide whether each of the statements is or is not correct (you may find it helpful to put a tick against the statements that you consider to be correct). The responses A to D should be selected on the basis of No other combination of statements is used as a correct response. 31 It is suggested that the solid deposits of ammonium compounds on the leaves of trees found in areas of high pollution are caused by the following reaction. 2NH3 + SO3 + H2O →(NH4)2SO4 Which of these take place in this reaction? 1 an acid-base reaction 2 ionic bond formation 3 oxidation and reduction 32 One explanation of the explosion at the Chernobyl nuclear power plant in 1986 is that the graphite reactor overheated and reacted with the cooling water according to the following equation. C(s) + H2O(g) H2(g) + CO(g) ∆H = + 131 kJ mol–1 What are possible reasons why the forward reaction is more likely to occur at high temperature? 1 Hydrogen and carbon monoxide do not react at high temperature. 2 At lower temperature, the position of equilibrium lies too far to the left. 3 The energy of activation is high. A B C D 1, 2 and 3 1 and 2 2 and 3 1 only are only are only are is correct correct correct correct

12 9701/1/O/N/03 The responses A to D should be selected on the basis of No other combination of statements is used as a correct response. 33 The diagram represents the Boltzmann distribution of molecular energies at a given temperature. As temperature increases, which statements are correct? 1 The maximum of the curve is displaced to the right. 2 The proportion of molecules with energies above any given value increases. 3 The proportion of molecules with any given energy increases. 34 Which statements concerning the third period elements (sodium to argon) and their compounds are correct? 1 The elements become more electronegative from sodium to chlorine. 2 Aluminium oxide is the only oxide which is insoluble in water. 3 The maximum oxidation state is shown by silicon. 35 A farmer spreads lime on land which has already been treated with a nitrogenous fertiliser. Which reactions will occur over a period of time? 1 Ca(OH)2 + CO2 →CaCO3 + H2O 2 Ca(OH)2 + 2H+(aq) →Ca2+(aq) + 2H2O 3 Ca(OH)2 + 2NH+ 4(aq) →Ca2+(aq) + 2NH3 + 2H2O energy proportion of molecules A B C D 1, 2 and 3 1 and 2 2 and 3 1 only are only are only are is correct correct correct correct

13 9701/1/O/N/03 [Turn over 36 Which processes involve the conversion of sulphur dioxide into sulphur trioxide? 1 the combustion of sulphur contaminated carbonaceous fuels 2 the Contact process for manufacturing sulphuric acid 3 the catalytic oxidation of sulphur dioxide by oxides of nitrogen 37 Which molecules would be present in the photochemical chlorination of methane? 1 hydrogen 2 hydrogen chloride 3 dichloromethane 38 The taste buds on the tongue are chiral and can distinguish one optical isomer from another. Which naturally-occurring compounds will have optical isomers that may be distinguished by taste? 39 The compound shown is a hormone produced during pregnancy to suppress ovulation. Which reagents would give positive results with this compound? 1 aqueous bromine 2 2,4-dinitrophenylhydrazine 3 Fehling’s reagent O CH3 CH3 CH3 C O CH C H OH O C H OH C H OH CH2OH 1 2 3 CH3 CH3 CH3 CH OH ribose menthol maleic acid HO C O O C CH OH CH

14 9701/1/O/N/03 The responses A to D should be selected on the basis of No other combination of statements is used as a correct response. 40 The flavour of pineapples is partly due to the compound Q. When Q is heated under reflux with NaOH(aq) and the mixture distilled, what compounds will be found in the distillate? 1 CH3OH 2 CH3CH2CH2CO2Na 3 CH3CH2CH2OH CH3CH2CH2COCH3 O Q A B C D 1, 2 and 3 1 and 2 2 and 3 1 only are only are only are is correct correct correct correct