SRJC H2 CHEM P1

1 SERANGOON JUNIOR COLLEGE General Certificate of Education Advanced Level Higher 2 CHEMISTRY 9746/01 Preliminary Examination 28 Aug 2009 Paper 1 MCQ 1 hour Additional Materials: OMS Data Booklet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid on the OMS. Write your name and index number on the OMS 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 OMS Follow the instructions given to you on how to fill in the OMS. 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 16 printed pages and 0 blank page SRJC 2009 9746/H2/PRELIM/01 [Turn over

2 SRJC 2009 9746/H2/PRELIM/01 [Turn over Answer ALL Questions 1 3.920 g of an oxide of formula MO was completely dissolved in 30.0 cm 3 of 2.00 mol dm -3 sulphuric acid. The resulting solution was made up to 100 cm 3. 25.0 cm 3 of this solution was neutralised by 27.5 cm 3 of 0.100 mol dm-3 sodium hydroxide. What is the relative atomic mass of M? A 47.9 B 54.9 C 55.9 D 101.0 2 A commercial production of iodine involves the reduction of a solution of iodate(V) ions, IO3 , with the theoretical quantity of hydrogen sulphite ions, HSO 3  in acidic condition. The hydrogen sulphite ions are oxidised to sulphate ions, SO 4 2 while the iodate( V) ions are reduced to iodine, I2. Given H2O(l) + HSO3 ─(aq) → SO4 2─(aq) + 3H+(aq) + 2e─ How many moles of hydrogen sulphite ions are needed to r educe one mole of iodate(V) ions? A 0.4 B 1 C 2.5 D 5 3 One of the isotopes of carbon is carbon-14. Carbon-14 is radioactive and is used in carbon dating by archaeologists. Which one of the following species is isotonic and isoelectronic with respect to an atom of carbon-14? A 13C B 14N+ C 16O2+ D 17F+

3 SRJC 2009 9746/H2/PRELIM/01 [Turn over 4 Which of the following shows a graph of  P against T for an ideal gas? (P = pressure;  = density; T = temperature in C).  P  P 5 Polyurethane is used in coatings, insulators and adhesiv es. Polyurethane What are the values of the bond angles marked a and b in polyurethane? a b A 90 90 B 120 120 C 107 120 D 109.5 90 A T T B  P  P T T C D C O N H CC H H H H N H C O OCC H H H H O b a n

4 SRJC 2009 9746/H2/PRELIM/01 [Turn over 6 Zinc oxide reacts with hydrogen according to the following equation. ZnO (s) + H2 (g) Zn (s) + H2O (g) At temperature T and a total pr essure of 10 atm, it is fo und that initial amounts of 1 mole of zinc oxide and hydrogen gas each produce 0.01 mole of zinc and steam at equilibrium. What is the approximate value of K p at temperature T? A 10-4 B 10-2 C 10 D 100 7 Hydrogen peroxide reacts with acidified iodide ions liberating iodine according to the equation below: H 2O2 (aq) + 2H+ (aq) + 2I- (aq)  I2 (aq) + 2H2O (l) The kinetics of this reaction were investigated and it was found to have the following rate equation: rate = k [H 2O2] [I-] Two series of experiments were conducted giving rise to Graph A and Graph B. Graph A Graph B rate of reaction/ mol dm-3 s-1 y x time Which of the following shows the co rrect labeling of the x-axis for Graph A and y-axis for Graph B? x-axis for Graph A y-axis for Graph B A [H2O2] [I -] / mol2 dm-6 [H +] / mol dm-3 B [I -] [H+] / mol2 dm-6 [ I 2] / mol dm-3 C [H2O2] / mol dm-3 [I -] / mol dm-3 D [H+] / mol dm-3 [H 2O2] / mol dm-3

5 SRJC 2009 9746/H2/PRELIM/01 [Turn over 8 An enzyme was found to operate at maxi mum efficiency in an aqueous solution buffered at pH 5. Whi ch of the following would give the necessary buffer solution when dissolved in 10 dm3 of water? A 1 mol of NaOH and 1 mol of CH3COOH B 1 mol of CH3COOH and 1 mol of CH3COO–Na+ C 1 mol of HCl and 1 mol of CH3COO–Na+ D 1 mol of CH3COO–NH4 + 9 When the concentration of Ca2+ ions in water is greater than 10-5 mol dm-3, an insoluble scum would be formed with soap. To prevent scum forming with s oap, what minimum mass of sodium carbonate should be added to 1 dm3 of water? [Solubility product of CaCO3 = 5.0 x 10-9 mol2 dm-6] A 0.037 g B 0.042 g C 0.050 g D 0.053 g 10 The enthalpy change of neutralisat ion of dilute sulphuric acid by dilute sodium hydroxide is the heat liberated when A 1 mole of H2SO4 reacts with ½ mole of NaOH B 1 mole of H2SO4 reacts with 1 mole of NaOH C 1 mole of H2SO4 reacts with 2 mole of NaOH D ½ mole of H2SO4 reacts with 1 mole of NaOH

6 SRJC 2009 9746/H2/PRELIM/01 [Turn over C 11 Tetrachloroethene is c ommonly used as a degr easing solvent. The enthalpy change for the reaction below is -878.5 kJ mol-1. 2H4 (g) + 4HCl (g) + 2O2 (g) → C2Cl4 (l) + 4H2O (l) Which of the following is the enthalpy change of formation of tetrachloroethene given the following information? ∆Hf (C2H4 (g)) = +52.3 kJ mol-1 ∆Hf (HCl (g)) = -92.3 kJ mol-1 ∆Hf (H2O (l)) = -285.8 kJ mol-1 A -9.2 kJ mol-1 B -52.2 kJ mol-1 C -330 kJ mol-1 D -633 kJ mol-1 12 Given the cell diagram, Cu (s) / Cu2+ (aq) // Ag+ (aq) / Ag (s) Which of the following statement is correct? A The mass of the silver electrode will decrease. B Electrons flow from the silver electrode to the copper electrode in the external circuit. C When NaOH(aq) is added to the Cu2+(aq)/Cu(s) half cell, the E cell will become less positive. D Replacing the Ag +(aq)/Ag(s) half cell with Co 2+(aq)/Co(s) half cell will reverse the direction of electron flow in the external circuit.

7 SRJC 2009 9746/H2/PRELIM/01 [Turn over 13 A current of 0.2 A passing for 5 hours throu gh a solution of gold ions deposits a mass of 2.45 g of gold on the cathode. Which of these expressions gives the charge on a gold ion? A 2.45×0.2×5×60×60 197×96500 B 0.2 5 60 60 197 96500 2.45     C 2.45 96500 1 9 70 . 256 06 0     D 197 0.2 5 60 96500 2.45   

8 SRJC 2009 9746/H2/PRELIM/01 [Turn over 14 The following shows the variatio n of a property of the first 20 elements in the Periodic Table with the proton number of the element. What is the property? A Atomic radius B First ionisation energy C Ionic radius D Melting point Property 15 Which of the following elements has an oxide with a giant structure and a chloride which is readily hydrolysed? A Silicon B Sodium C Phosphorus D Carbon

9 SRJC 2009 9746/H2/PRELIM/01 [Turn over 16 Which of the statements about Group II elements is correct? A The reducing power decreases down the group. B The ionic r adius increases down the group. C The electronegativity increases down the group. D The reactivity with water decreases down the group. 17 The solubility of the Group II sulphates decreases as the prot