CJC H2 CHEM P1 Prelim

CATHOLIC JUNIOR COLLEGE Preliminary Examination 2009 Higher 2 CHEMISTRY 9746/01 Paper 1 Multiple Choice 17 September 2009 1 hour Additional Materials: Multiple Choice Answer Sheet Data Booklet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use correction fluid. Write your name and class on the MCQ Answer Sheet in the spaces provided. 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 MCQ 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. This document consists of 13 printed pages and 1 blank page. CJC Chemistry Department © CJC 2009

 CJC 2009 9746/01/prelim/09 2 For each question there are four possible answers, A, B, C and D. Choose the one you consider to be correct and record your choice in soft pencil on the separate answer sheet provided. 1 Which statement about one mole of a gas is always true? A It has the same mass as one mole of hydrogen gas. B It contains the same number of particles as 1/12 mole of 12C C It occupies the same volume as one mole of ethane gas under the same conditions. D It undergoes a redox process involving transfer of one mole of electrons. 2 The following diagram illustrates the variation of a physical property with increasing atomic number across a certain Period. Which of the following is the physical property sh own? A atomic radius B melting point C first ionisation energy D electrical conductivity 3 Which of the following is not a disproportionation reaction? A Cu 2O(s) + H2SO 4(aq) → Cu(s) + CuSO 4(aq) + H2O(l) B 2 NaOH(aq) + C l2(aq) → NaC l(aq) + NaC lO(aq) C 2 H 2S(g) + SO 2(g) → 3 S(s) + 2 H2O(g) D 2 H 2O2(aq) → 2 H2O( l) + O2(g) 4 25.0 cm 3 of a 0.0200 mol dm -3 solution of a compound of element D is reduced by reaction with Sn, which is oxidised to Sn 2+ in the process. If the resulting solution required 10.0 cm 3 of 0.0200 mol dm -3 of acidified KMnO 4 to oxidise D back to its original oxidation state, what is the mass of tin required in the first reaction? A 0.0100 g B 0.0238 g C 0.0357 g D 0.0595 g atomic no.

 CJC 2009 9746/01/prelim/09 3 5 Chlorine has two isotopes, 35 Cl and 37 Cl. In an experiment, a sample of chlorine was vapourised and ionised at high temperatures and passed through an electric field. The following sets of deflections were observed. Which of the species could have produced the series of lines in set I? A 35 Cl+, 37 Cl+ B 35 Cl+, 37 Cl2 + C 37 Cl+, 37 Cl2 + D 35 Cl2 +, 35 Cl37 Cl+, 37 Cl2 + 6 Which of the following sets consists of two ionic c ompounds and one simple covalent compound? A MgO, A l2O3, SiC B A lCl3, PCl5, P 4O10 C Na 2O, A lF3, SO 3 D BaO, SiO 2, SiCl4 7 Which of the following pairs does species I have a smaller bond angle than species II ? I II A NO 2 - NO 3 - B CS 2 SO 4 2- C PH 4 + SF 6 D AsC l3 C lO2 - 8 Dinitrogen oxide, N=N=O, burns in ethyne, C 2H2, in the gaseous phase to produce water vapour, carbon dioxide and nitrogen gases as the only products. 5 N 2O(g) + C 2H2(g) → H 2O(g) + 2 CO 2(g) + 5 N 2(g) ΔH = -1668 kJ mol -1 Assuming N=N bond energy in dinitrogen oxide is +41 8 kJ mol -1, what is the nitrogen- oxygen bond energy in dinitrogen oxide in kJ mol -1? A 382 B 594 C 686 D 1350 source - + Se t I Set I I

 CJC 2009 9746/01/prelim/09 4 9 In oil refineries, an important process is the recovery of any sulfur from petroleum. 2 H 2S(g) + O2(g) → 2 H 2O(g) + 2 S(s) The enthalpy changes of formation of H 2S(g) is -20.5 kJ mol ─1 and that of H 2O(g) is -243 kJ mol ─1. Which statement is true ? A The above reaction is thermodynamically feasible only at low temperatures. B Enthalpy change of combustion of H 2S is -445 kJ mol -1. C The enthalpy change of vapourisation of H 2O is less endothermic than that of H2S. D The bond angle for H-S-H is larger than that of H- O-H. 10 Which one of the following statements about the properties of graphite is incorrect ? A It can be used as a lubricant because of the weak force of attraction between layers. B Each carbon atom is sp 2 hybridised. C It is a good conductor of electricity in the direc tion parallel to the planes containing hexagonal rings of carbon but a poor conductor perpendicular to these planes. D Carbon to carbon distances between the planes of hexagonal rings is the same as that of carbon to carbon distances within those planes. 11 0.1 g of dry hydrogen gas was placed in a closed 2 m 3 vessel with 3.2 g of oxygen gas. The gases were exploded and the system was allowed to cool to 25 ° C. What will be the pressure, in Pa, of the gas left in the vessel after the reaction? (The volume and vapour pressure of water may be neglected ) A 56.7 B 61.9 C 92.9 D 123.8 12 When 0.20 mol of hydrogen gas and 0.15 mol of iodi ne 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) 2 H I(g) What is the correct expression for the equilibrium constant, K c? A 15 . 020 . 0 26 . 02 × × B 15 . 020 . 0 )26 . 02 ( 2 × × C 02 . 007 . 0 )26 . 0 (2 × D 13 . 013 . 0 )26 . 0 (2 × 13 Use of the Data Booklet is relevant to this question . Many laboratory spatulas are made of nickel. Which aqueous solution might react with a nickel spatula? A Cu 2+ (aq) B Co 2+ (aq) C Mn 2+ (aq) D Fe 2+ (aq)

 CJC 2009 9746/01/prelim/09 5 14 When a quantity of electricity was passed through m olten scandium oxide, 5.00 g of scandium and 2.67 g of oxygen were produced at the electrodes. What is the formula of scandium oxide? A ScO 3 B ScO C Sc 2O3 D Sc 3O2 15 The diagram shows the Boltzmann distribution of the speeds of the molecules of a gas. Point X represents the most probable speed. If the gas is cooled, in which direction does X move? 16 When 0.010 mol of an unknown compound was complete ly dissolved in 1.0 mol dm -3 of water, the resulting solution was found to have a p H of 4.0. What is the identity of this compound? A H I B NaOH C CH 3CH 2NH 2 D C lCH 2CO 2H 17 Which graph correctly describes a trend found in G roup VII? A B C D X–X bond energy Cl 2 Br 2 I2 boiling point of X 2 Cl 2 Br 2 I2 X–X bond length Cl 2 Br 2 I2 strength of intermolecular forces Cl 2 Br 2 I2 proportion of molecules speed X D C B A

 CJC 2009 9746/01/prelim/09 6 • 18 M is a transition metal. In aqueous solution, it forms the complex ion, [ M(H 2O) 6]3+ . On oxidation of [ M(H 2O) 6]3+ to [ M(H 2O) 6]4+ , the solution turned colourless. Which of the following is the electronic configuration of the transition metal M? A [Ar] 3d 1 4s 2 B [Ar] 3d 2 4s 2 C [Ar] 3d 3 4s 2 D [Ar] 3d 10 4s 2 19 Athletes preparing for the Youth Olympics Games (Y OG) in 2010 follow a high- carbohydrate diet to maintain high-intensity exercise for a longer period. Glucose is an important carbohydrate in biology as the living cell uses it as a source of energy and metabolic intermediate. glucose How many stereoisomers does glucose exhibit? A 2 1 B 22 C 23 D 2 4 20 The equation below represents the sulfonation of b enzene under suitable conditions. + H 2SO 4