TJC Prelim P1

TEMASEK JUNIOR COLLEGE CHEMISTRY 9746/01 Paper 1 Multiple Choice Tuesday 29th SEPTEMBER 2009 1 hour Additional materials: Data Booklet Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Do not open this booklet until you are told to do so. Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, index number and CG on the Answer Sheet in the spaces provided. There are forty questions on this paper. Answer all questions. For each question, there are four possible answers labelled 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. You may use a calculator. This document consists of 19 printed pages. [Turn over

2 TJC H2 Chemistry Paper 1 2009 [Turn over Section A For each question there are four possible answers, A, B, C and D . Choose the one you consider to be correct. 1 Given the following information: Hc (graphite) = -394 kJ mol-1 Hf (water) = -286 kJ mol-1 Hf (methanol) = -239 kJ mol-1 Which one of the following is the correct H c (methanol) in kJ mol-1? A -441 B -727 C -919 D -1205 2 In an experiment, 10 cm3 of an organic compound X in the gaseous state was sparked in excess oxygen. 20 cm 3 of carbon dioxide and 5 cm 3 of nitrogen were obtained among the products. All gas volumes were measured at the same temperature and pressure. Which of the following compounds could be X? A C 2H7N B C2H6N2 C C6H5NO2 D C3H5N

3 TJC H2 Chemistry Paper 1 2009 [Turn over 3 Ozone reacts with nitric oxide according to the equation: NO(g) + O3(g)  NO2(g) + O2(g) 0.66g of NO(g) was mixed with 0.72g of O 3(g). What is the maximum volume of NO2(g) produced at 0C and 100 kPa? A 0.34 dm3 B 0.37 dm3 C 0.45 dm3 D 0.50 dm3 4 Why is ethanoic acid a stronger acid in liquid ammonia than in aqueous solution? A Ammonia is a stronger base than water B Ammonium ethanoate is completely ionised in aqueous solution C Ammonium ethanoate is strongly acidic in aqueous solution D Liquid ammonia is a more polar solvent than water. 5 An acidified solution containing 0.10 mol dm -3 of zinc sulphate and 0.10 mol dm -3 of copper (II) sulphate is saturated with hydrogen sulphide at 15 oC. The concentration of S2- (aq) in the solution is then 10-35 mol dm-3. The solubility product of zinc sulphide at 15 oC is 10-24 mol2dm-6 and that of copper (II) sulphide is 10-40 mol2dm-6. Which statement describes what happens in the solution? A No precipitate is formed. B Copper (II) sulphide only is precipitated. C Copper (II) sulphide is precipitated followed by zinc sulphide. D Zinc sulphide is precipitated followed by copper (II) sulphide.

4 TJC H2 Chemistry Paper 1 2009 [Turn over 6 AlCl3 reacts with LiA lH4 and (CH 3)3NAlH3. Which statements about (CH 3)3NAlH3 is correct? A It contains hydrogen bonding B It is dimeric C The Al atom is electron deficient D The bonds around the Al atom are tetrahedrally arranged 7 When 0.20 mol of hydrogen gas and 0.15 mol of iodine gas are heated at 723 K until equilibrium is established, the equilibrium mixture is found to contain 0.26 mol of hydrogen iodide. The equation for the reaction is as follows. H 2(g) + I2(g) 2HI(g) What is the correct expression for the equilibrium constant Kc? A 2 x 0.26 __ 0.20 x 0.15 B (2 x 0.26)2 0.20 x 0.15 C (0.26)2___ 0.07 x 0.02 D (0.26)2___ 0.13 x 0.13

5 TJC H2 Chemistry Paper 1 2009 [Turn over 8 Ions of the two most common isotopes of the transition metal nickel are shown below: 2Ni58 28 2Ni 60 28 Which one of the following statements is true? A The electron arrangement of both these Ni2+ ions is 1s22s22p63s23p63d64s2. B The ion will have more protons in its nucleus than the ion. 2Ni 60 28 2Ni58 28 C In the same strength magnetic field, the ion will be deflected more than the ion. 2Ni 60 28 2Ni58 28 D Both of these Ni 2+ ions have the same number of electrons but a different number of neutrons. 9 Which of the following conversions involves an oxidation of vanadium? A VF5  V 2O5 B VO2+  V 2+ C VO2+  V 3+ D VO2+  VO 2 +

6 TJC H2 Chemistry Paper 1 2009 [Turn over 10 Substances X, Y and Z react according to the following equation: X(aq) + 2Y(aq) + Z(aq) → 2W(aq) + U(aq) To find the rate equation for the above reaction, two sets of separate experiments were performed, in which the initial concentrations of each of the reactants X, Y and Z were varied in turn, the other two being kept constant. The results are shown below. If k is the rate constant, the rate equation is most likely to be: A rate = k[X][Y][Z] B rate = k[X][Y]2[Z] C rate = k[Y]2[Z] D rate = k[Y][Z] 11 A Fe 3+/Fe2+ half-cell was connected to a Ni 2+/Ni half-cell as shown in the diagram below under standard conditions. Which of the following statements is incorrect? A The solution in the Fe3+/Fe2+ half cell turns green. B The standard cell potential is +1.02 V. C The electron flows from the Ni2+/Ni half cell to the Fe3+/Fe2+ half cell. D The cathode decreases in size. Ni 1.0 mol dm-3 Ni2+(aq) 1.0 mol dm-3 , Fe3+(aq), Fe2+(aq) Pt Salt bridge V

7 TJC H2 Chemistry Paper 1 2009 [Turn over 12 Which factors determine the number of atom s of copper deposited on the cathode of an electrolytic cell? [Ag+aq] current Time A √ x x B x √ √ C √ √ x D √ √ √ 13 When a sample of 0.01 mol of hydrocarbon was completely burnt in oxygen, 2.20 g of carbon dioxide gas was formed at room temperature and pressure. The same amount of hydrocarbon is also found to react with 50 cm3 of 0.4 mol dm3 of aqueous bromine. Which of the following could this hydrocarbon be? A CH3CHCHCH3 B CH2CHCH2CH3 C CH2CHC(CH3)CH2 D CH(CH3)CHCH2CH3

8 TJC H2 Chemistry Paper 1 2009 [Turn over 14 Geraniol has a rose-like odour and is commonly used in perfumes. geraniol Which of the following is not formed when geraniol reacts with hot acidified potassium managanate(VII)? A B (CO2H)2 C D 15 Compound P can be converted to compound Q in a sequence of steps. Which of the following statements is correct? A The sequential conversion of P to Q involves a nucleophilic substitution reaction, acidic hydrolysis and esterification. B Compound P must be converted into an alkene first in the first step of conversion to compound Q. C When hot aqueous alkaline iodine is added to separate samples of P and Q, only compound P forms a yellow precipitate. D When hot aqueous sodium hydroxide is added separately to compounds P and Q, only compound P gives a pale yellow precipitate when added to silver nitrate solution. Br O2N C CH3 CH3 Br Br O2N C CH3 CH3 OOCCH3 P Q

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