DHS H2 Chem 2013 Prelim P1 QP

1 This question paper consists of 18 printed pages and 0 blank page © DHS 2013 [ T u r n o v e r Name: Index Number: Class: DUNMAN HIGH SCHOOL Preliminary Examination Year 6 H2 CHEMISTRY 9647/01 Paper 1 Multiple Choice 27 September 2013 60 minutes Additional Materials: Optical Mark Sheet Data Booklet INSTRUCTIONS TO CANDIDATES 1 Write your name, index number and class on this question paper. 2 There are forty questions in 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 Optical Mark Sheet. 3 Each correct answer will score one mark. A mark will not be deducted for wrong answer. 4 Any rough working should be done in this booklet. 5 You may use a calculator.                 473

2 © DHS 2013 9647/01 [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 A 1.0 g sample containing 0.0065 mol of organoboron compound, with the formula CxHyBOz, was burnt in an excess of oxygen. The carbon dioxide and steam produced were passed into solid NaOH and P 2O5, which increased in mass by 2.29 g and 0.877 g respectively. What is the molecular formula of the organoboron compound? A CH2BO2 B C8H7BO2 C C8H15BO2 D C9H15BO 2 SO2 gas is found in air near volcanoes. 218.4 cm 3 of SO 2 collected at s.t.p. near a volcano was reacted with 25.0 cm3 of 0.130 mol dm–3 acidified potassium dichromate solution to turn the solution from orange to green. What is the oxidation state of sulfur at the end of the reaction? A 0 B +2 C +4 D +6 3 Varying volumes of H 2O2 of an unknown concentration was reacted with varying volumes of 0.50 mol dm –3 acidified potassium manganate( VII) in a series of experiments, to produce the graph below. The total volume of solutions used in each experiment was 100 cm 3. In each experiment, the difference between the highest temperature reached and the initial temperature was calculated, and was plotted against the volume of H2O2 used. What is the concentration of H2O2 and the enthalpy change of the reaction per mole of H2O2? Assume specific heat capacity of the solution is 4.2 J g –1 K–1 and the density of the solution is 1 g cm-3. [H2O2] Enthalpy change of reaction A 0.536 mol dm–3 +151 kJ mol–1 B 0.214 mol dm–3 +378 kJ mol–1 C 0.536 mol dm–3 +378 kJ mol–1 D 0.214 mol dm–3 +151 kJ mol–1 ∆T/ ºC Volume of H2O2/ cm3 70 13.5 474

3 © DHS 2013 9647/01 [Turn over 4 Elements W, X, Y and Z are four consecutive elements in the Periodic Table. The following table shows the first four ionisation energies of each element. Element 1 st I.E 2 nd I.E 3 rd I.E 4 th I.E W 1685 3374 6050 8408 X 2081 3952 6122 9371 Y 496 4562 6910 9543 Z 738 1451 7733 10543 Which Groups do elements W and Z belong to? W Z A Group VII Group II B Group V Group I C Group III Group VI D Group I Group IV 5 Four ions of unknown elements are given below. Which of the following correctly shows a pair of isotopic and isoelectronic species? Isotopic Isoelectronic A P2–, Q3– N–, Q3– B N–, P2– M+, N– C N–, P2– N–, Q3– D P2–, Q3– M+, N– 6 Given the following reaction: A (g) + B (g 2C (g) + 2D (g) Kp = 2.10 x 102 atm2 An equimolar mixture of A and B is allowed to reach equilibrium at 700 K. Determine the total pressure at equilibrium if the partial pressure of C at equilibrium is found to be 2.00 atm. A 1.28 atm B 4 atm C 4.28 atm D 4.56 atm M 21 10 2− 11 20 NP 20 9 − 9 21Q + 3− 475

4 © DHS 2013 9647/01 [Turn over 7 The following shows a graph of effective nuclear charge against proton number for elements in Period 3 of the Periodic Table, from sodium to chlorine. Which of the following trends cannot be inferred from the graph above? A Atomic radii decrease across the period. B Electron affinity increase across the period. C Electronegativity increase across the period. D Electrical conductivity decrease across the period. 8 When bromoethane reacts with alcoholic potassium hydroxide to produce ethene, the overall equation and rate equation are given as follows. CH3CH2Br + OH– → CH2=CH2 + H2O + Br– rate = k[CH3CH2Br][OH–] Which of the following statement is consistent with the rate equation? A The units of the rate constant k are mol–2 dm–6 s–1 . B This is an elementary reaction as intermediates are formed. C When bromoethane reacts with excess KOH, the half life of bromoethane is halved if [KOH] is doubled. D The graph of [CH 3CH2Br] against time shows a constant half life, indicating first order of reaction with respect to KOH. 0 1 2 3 4 5 6 7 1234567 Effective Nuclear Charge Na Mg A l Si P S C l 476

5 © DHS 2013 9647/01 [Turn over 9 Which of the following reactions of first row transition metal ions is correct? A Addition of Na2CO3(aq) to FeCl3(aq) produces a brown precipitate of Fe2(CO3)3. B Addition of KI(aq) to CuSO4(aq) produces a blue precipitate of CuI2. C Addition of KOH to K2CrO4(aq) produces an orange solution of K2Cr2O7. D Addition of concentrated HC l to CuSO 4(aq) produces a yellow solution of H2[CuCl4]. 10 The table below describes the solubilities of magnesium and barium sulfates and hydroxides in water. Solubility of sulfates in water Solubility of hydroxides in water Mg2+ Soluble Sparingly soluble Ba2+ Sparingly soluble Soluble Which of the following is not true? A Enthalpy change of solution is likely to be exothermic for magnesium sulfate but endothermic for barium sulfate. B The enthalpy change of hydration for barium cations is more exothermic than for magnesium cations. C Magnesium sulfate is more soluble than barium sulfate as enthalpy change of hydration becomes less exothermic down the group. D Barium hydroxide is more soluble than magnesium hydroxide as lattice energy of the ionic solid is less exothermic down the group. 11 Which of the following statements about strontium and palladium is true? A The atomic radius of palladium is smaller than strontium as the d electrons in palladium provide effective shielding against the nuclear charge. B Palladium, with a larger number of vale nce electrons, has stronger electrostatic forces of attraction between its cations and electrons. C Strontium has a maximum oxidation state of +2 while palladium has a maximum oxidation state of +5. D There are more atoms per unit volume of strontium, compared to palladium. 477

6 © DHS 2013 9647/01 [Turn over 12 In an experiment, a cell is set up to obtain pure nickel from a nickel-silver alloy as shown below. When a current of 40.0 A flows through the electrolyte for 26.8 minutes, the mass of the anode changes by 50 g. Which of the statement is correct? A Electrode R is pure nickel and electrode S is the nickel-silver alloy. B The concentration of NiSO4(aq) decreases during the experiment. C The mass of the cathode changes by 50 g during the experiment. D The nickel-silver alloy contains 39% of nickel by mass. 13 Which of the following does not show a possible reaction between a halide and concentrated H2SO4? A 6HI + H2SO4 → 3I2 + S + 4H2O B 2HI + H2SO4 → I2 + SO2 + 2H2O C NaCl + H2SO4 → NaHSO4 + HCl D 8HBr + H2SO4 → 4Br2 + H2S + 4H2O NiSO 4(aq) electrode R electrode S 478

7 © DHS 2013 9647/01 [Turn over 14 The table below shows the reactions of some halogens with sodium thiosulfate and hydrogen. Halogen Reaction with Na 2S2O3 Reaction with H2 Chlorine 4Cl2 + S2O3 2– +