DHS Prelim H2 CHEM P1 QP

1 This question paper consists of 18 printed pages and 0 blank page. © DHS 2016 [Turn over Name: Index Number: Class: DUNMAN HIGH SCHOOL Preliminary Examinations 2016 Year 6 H2 CHEMISTRY 9647/01 Paper 1 Multiple Choice 27 September 2016 1 hour Additional Materials: Optical Mark Sheet Data Booklet INSTRUCTIONS TO CANDIDATES 1 Write your name and class on this question paper. 2 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 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.

2 © DHS 2016 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 Ferrous sulfate (FeSO 4) tablets are commonly prescribed by doctors as 350 mg tablets and serve as a dietary supplement for pregnant women. However, it was found that these tablets may cause poisoning in young children if accidentally consumed. The lethal dosage for a 12.0 kg child is 590 mg of Fe2+. What is the minimum number of tablets that would constitute a lethal dose to a 12.0 kg child? A 1 B 2 C 4 D 5 2 25.0 cm 3 of a solution of 0.0518 mol dm –3 hydroxylammonium chloride, NH 3OH+Cl– was added to a solution containing an excess of acidified Fe 3+ ions and the mixture boiled. The Fe2+ ions in the resultant solution was titrated with 25.90 cm 3 of 0.02 mol dm–3 potassium manganate (VII) solution. Given the mole ratio MnO 4– ≡ 5Fe 2+, which of the following nitrogen –containing species is formed in the reaction? A NH4+ B N2O C NO2 D NO3– 3 Two elements, Y and Z, have the following properties. Property 1: Y and Z form ionic compounds Na3Y and Na3Z respectively. Property 2: Element Z forms ZCl5 molecule whereas Y is unable to form YCl5. Which pair of electronic configurations of Y and Z is correct? Y Z A [He] 2s2 2p2 [Ne] 3s2 3p3 B [He] 2s2 2p3 [Ne] 3s2 3p3 C [He] 2s2 2p2 [He] 2s2 2p3 D [Ne] 3s2 3p2 [Ne] 3s2 3p3

3 © DHS 2016 9647/01 [Turn over 4 For one mole of an ideal gas, which plot produces a straight line graph passing through the origin? Y–axis X–axis A PV P at constant T (K) B P V at constant T (K) C P/ρ T (C) at constant V D P 1/V at constant T (K) 5 Use of Data Booklet is relevant to this question. Which substance is considered to have the largest covalent character? A AlF3 B Al2O3 C Be3N2 D BeO 6 Which substance does not contain an atom that has an unpaired electron? A ClO2 B NO C NO2 D N2O 7 Ammonia is made via the Haber Process. The reactants are nitrogen and hydrogen. N2(g) + 3H2(g) 2NH3(g) ∆H = –92 kJ mol−1 What will increase the rate of the forward reaction? A Adding argon to the mixture but keeping the total volume constant. B Decreasing the temperature. C Increasing the total pressure by reducing the total volume at constant temperature. D Removing nitrogen from the mixture but keeping the total volume of the mixture the same. 8 How much water must be added to a 10 cm 3 solution of 0.05 mol dm –3 sulfuric acid in order to increase its pH to 2.0? A 10 cm3 B 50 cm3 C 90 cm3 D 100 cm3

4 © DHS 2016 9647/01 [Turn over 9 Given that the Ksp for magnesium hydroxide, Mg(OH) 2, is 1.80 x 10 –11 mol3 dm–9 at 298 K, calculate the pH of a saturated solution of Mg(OH)2. A 3.48 B 3.78 C 10.2 D 10.5 10 The reaction of nitrogen monoxide and hydrogen gas 2NO(g) + 2H2(g)  N2(g) + 2H2O(g) is hypothesised to involve the following steps: I NO + NO N2O2 (fast) II N2O2 + H2  H2O + N2O (slow) III N2O + H2  N2 + H2O (fast) Which of the following is true about the reaction? A H2 acts as a catalyst in this reaction. B The overall order of the reaction is 2. C There are 2 intermediates present in the reaction mechanism. D Increasing the concentration of NO will increase the rate constant. 11 The radius and charge of each of the six ions are shown in the table. ion J+ L+ M2+ X– Y– Z2– radius / nm 0.14 0.18 0.15 0.14 0.18 0.15 Which of the following pair shows the first compound having a smaller magnitude of lattice energy than the second? A JX, MZ B JX, LX C JY, LX D MZ, LY

5 © DHS 2016 9647/01 [Turn over 12 The common rubber band has very interesting thermodynamic properties due to its randomly coiled long polymeric molecular structure. When the rubber band is stretched, a slight warming effect is felt. What are the correct signs of ∆S, ∆H and ∆G if the stretched rubber band is releas ed quickly? ∆S ∆H ∆G A + + – B + – + C – – + D – + – 13 The nickel –cadmium cell is a rechargeable battery which contains an alkaline electrolyte such as aqueous KOH. During the discharging process, Cd is oxidised to solid Cd(OH)2 while NiO(OH) is reduced to solid Ni(OH)2. Which statement is true about this rechargeable battery? A Water is produced in the discharging process. B The mass of cadmium remains unchanged. C The alkaline electrolyte can be replaced by an acid. D The concentration of the alkaline electrolyte remains unchanged in the discharging process. 14 Which statement regarding the oxides across Period 3 is true? A The covalent character decreases from Na to S. B The oxides of the elements changes from basic to neutral then to acidic from Na to S. C The oxides formed are increasing soluble in water from Na to S. D The standard entropy change of formation of the oxides becomes more negative from Na to Al.

6 © DHS 2016 9647/01 [Turn over 15 The following information is about a Period 3 element L. The oxide of L is a solid at room temperature. The oxide of L, when added to water, gives a non-acidic solution. The aqueous chloride of L gives a white precipitate with aqueous sodium hydroxide. In which Group of the Periodic Table could L be found? A V only B I and III only C II and III only D II, III and IV only 16 Which property shows an increasing trend down Group II from Mg to Ba? A Polarising power of metal cation B Second ionisation energy C Reducing strength D Melting point 17 Which statement regarding the halogens or their hydrides is correct? A HCl has a higher melting point than HF due to its larger electron cloud. B Iodine, when dissolved in hexane, gives a colour that is similar to its vapour. C The halogens become less volatile from fluorine to iodine due to the weaker covalent bonds. D HF is less thermally stable than H I because of the larger electronegativity difference between the H and F atoms.

7 © DHS 2016 9647/01