CJC Prelim P1 QP

1 CHEMISTRY 9729/01 Paper 1 Multiple Choice 29 August 2017 Additional Materials: Multiple Choice Answer Sheet Data Booklet READ THESE INSTRUCTIONS FIRST Write your name, HT group and NRIC/FIN number on the Answer Sheet in the spaces provided. Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. There are thirty 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. The use of an approved scientific calculator is expected, where appropriate. This document consists of 14 printed pages and 0 blank page. Catholic Junior College JC 2 Preliminary Examinations Higher 2

2 9729/01/CJC JC2 Preliminary Examination 2017 For each question there are four possible answers, A, B, C and D. Choose the one you consider to be correct. 1 When an unknown organic compound is burned completely in excess oxygen, 90 cm3 of gaseous products is collected. When cooled to room temperature, the gaseous volume decreased to 50 cm3. A further decrease of 40 cm3 in the gaseous volume was observed when the gaseous mixture is passed through aqueous potassium hydroxide. What is the possible identity of the organic compound? 1 CH2CH2 2 CH3CO2H 3 CH3CH2CH3 4 CH2CHCH2OH A 1 and 3 only B 1 and 4 only C 1, 2 and 4 only D 2 and 4 only 2 Use of the Data Booklet is relevant to this question. A vanadium salt of unknown oxidation state was dissolved in water to form a solution of 0.500 mol dm–3. It was found that 20.4 cm 3 of this solution will react with 1.00 g of zinc powder to form vanadium(II) solution. What is the possible identity of the vanadium salt used? A V2+ B V3+ C VO2+ D VO2+ 3 The table below gives some data about four ions. ions number of neutrons number of nucleons Q– 16 33 R+ 19 39 S2– 17 33 T2+ 18 35 Which of the following pairs consists of ions that are isoelectronic? A Q– and S2– C S2– and T2+ B R+ and S2– D Q– and T2+

3 9729/01/CJC JC2 Preliminary Examination 2017 [Turn over 4 Which bond angle is present in a molecule of alanine, H2NCH(CH3)CO2H, but is not present in its zwitterion? A 90 B 107 C 109 D 120 5 What are the types of chemical bonds present in solid phenylammonium chloride, C6H5NH3Cl? 1 dative covalent bonds 2 ionic bonds 3 hydrogen bonds A 2 only B 1 and 2 only C 2 and 3 only D 1, 2 and 3 6 Which one of the following shows the standard enthalpy change of formation of carbon monoxide? A C(s) + ½O2(g) → CO(g) B C(s) + CO2(g) → 2CO(g) C C(g) + ½O2(g) → CO(g) D C(g) + CO2(g) → 2CO(g)

4 9729/01/CJC JC2 Preliminary Examination 2017 7 Nitrogen dioxide, NO2, has an unpaired electron and dimerises to form N2O4. 2NO2(g) → N2O4(g) Which of the following statements about the spontaneity of the reaction is true? A The reaction is only spontaneous at low temperatures. B The reaction is only spontaneous at high temperatures. C The reaction is spontaneous at all temperatures. D The reaction is non-spontaneous at all temperatures. 8 Use of the Data Booklet is relevant to this question. Gas canisters used in camping stoves contain partially liquefied hydrocarbon. A canister was connected to a gas syringe and the valve opened slightly to allow some gas into the syringe. 0.200 g of the gas occupied a volume of 96.0 cm 3 at a temperature of 30.0 C and a pressure of 101 kPa. What is the average Mr of the gas mixture? A 31 B 52 C 479 D 519 9 At a certain temperature, three gases N 2, O 2 and HC l were mixed and the following reaction occurred: 2N2(g) + 3O2(g) + 4HCl(g) ⇌ 4NOCl(g) + 2H2O(g) The initial partial pressures of N2, O2 and HCl are 0.800 atm, 0.800 atm and 0.400 atm respectively. After equilibrium has been established, it is found that the partial pressure of steam is 0.15 atm. What is the numerical value of Kp for this reaction at this temperature? A 1.20 B 22.7 C 0.0217 D 0.0251

5 9729/01/CJC JC2 Preliminary Examination 2017 [Turn over 10 In an acid-base titration, a 0.10 mol dm -3 solution of an acid is added to a 25 cm 3 of a 0.10 mol dm-3 solution of a base. The pH value of the solution is plotted against the volume, V, of acid added as shown in the diagram. Which of the following statements is incorrect? A The titration involved a strong acid and a weak base. B The pair of solutions could have been HCl(aq) and CH3NH2(aq). C Methyl orange is a suitable indicator for the above titration. D When concentration of acid is doubled, the end point volume of the titration would be halved while the pH at equivalence point would remain unchanged. 11 The following two reactions are examples of acid-base reactions. Reaction 1: HNO3 + H2SO4 ⇌ H2NO3+ + HSO4– Reaction 2: NH3 + BF3  NH3BF3 Which of the following correctly describes the behaviour of each species? Brønsted acid Brønsted base Lewis acid Lewis base A HNO3 NH3 H2SO4 HSO4– B H2SO4 HNO3 BF3 NH3 C HSO4– NH3 BF3 H2NO3+ D H2NO3+ HSO4– NH3BF3 NH3

6 9729/01/CJC JC2 Preliminary Examination 2017 12 The decomposition of hydrogen peroxide is known to be a first order reaction. 2H2O2  2H2O + O2 The rate constant is found to be 4.95 x 10 –2 min–1. If the initial concentration of H 2O2 is 4.00 mol dm–3, what will be the concentration of H2O2 after 64 min? A 0.50 mol dm–3 C 0.17 mol dm–3 B 0.20 mol dm–3 D 0.13 mol dm–3 13 The rate equation for the reaction 2 W + X  Y + Z is given as r ate = k[ W][X]. In an experiment to study the kinetics of the reaction, the initial concentration of W used is 0.20 mol dm-3 and the initial concentration of X used is 0.001 mol dm-3. Which of the following statements regarding the experiment is correct? A The half-life for the [X] against time curve is approximately constant. B The mechanism for the above reaction involves one step. C The units of the rate constant is mol-2dm6s-1. D Doubling the initial concentration of W to 0.40 mol dm-3 will not affect the half-life of X. 14 The oxide and chloride of an element E are mixed separately with water. The two resulting solutions have the same effect on litmus. What is element E? A Mg B Al C Si D P 15 Which of the following statements about iodine or its compounds are correct? 1 A crystal of iodine contains covalent bonds and instantaneous dipole-induced dipole forces of attraction. 2 When aqueous chlorine is added to potassium iodide and the aqueous mixture shaken with tetrachloromethane, a purple organic layer is obtained. 3 The first ionisation energy of iodine is less than that of bromine. 4 The thermal stability of hydrogen iodide is higher than that of hydrogen bromide. A 1 and 3 only B 1, 2 and 3 only C 3 and 4 only D 2, 3 and 4 only

7 9729/01/CJC JC2 Preliminary Examination 2017 [Turn over 16 Aureomycin is a powerful oral antibiotics that is effective against a wide range of infections. Aureomycin Which row correctly indicates the number of chiral centres and sp2 hybridised carbon in a molecule of aureomycin? Number of chiral centres Number of sp2 hybridised C A 4 10 B 4 13 C 5 10 D 5 13 17 β-carotene is responsible for the orange colour of carrots. β-carotene is oxidised by hot, concentrated, acidified KMnO4. How many different products formed from the above reaction contain the ketone functional group? A 2 B 4