SAJC H2 CHEM P1 QP Prelim

1 [Turn Over ST ANDREW’S JUNIOR COLLEGE JC2 Preliminary Examinations Chemistry Higher 2 9647/01 19th September 2016 Paper 1 Multiple Choice 1 hour Additional Materials: Multiple Choice Answer Sheet, Data Booklet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. There are 40 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. Each correct answer will score one mar k. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet. This document consists of 27 printed pages including this page.

2 [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. What volume of CO 2 will be liberated when y cm3 of 40:60 mixture of volume of methane and ethene are completely burnt in oxygen? A y cm3 B 2y 5 cm3 C 8y 5 cm3 D 2y cm3 2. Use of the Data Booklet is relevant to this question. Ethanedioate ions, C 2O42–, are oxidised by acidified, aqueous potassium manganate( VII) to give carbon dioxide. What volume of 0.020 mol dm -3 potassium manganate( VII) is required to oxidise completely 1.0 x 10-3 mol of the salt NaHC2O4.H2C2O4? A 20 cm3 B 40 cm3 C 50 cm3 D 125 cm3

3 [Turn Over 3. Which graph correctly describes the behaviour of fixed masses of the ideal gases X and Y, where X has a higher Mr than Y? A B C D PV Constant P Y X T / K PV Constant P X Y P PV Constant T X Y PV P Constant T X Y T / C

4 [Turn Over 4. The table below shows the ionisation energy (in kJ mol -1) of four elements labelled A, B, C and D. Element 1st I.E. 2nd I.E. 3rd I.E. 4th I.E. 5th I.E. 6th I.E. A 1012 1907 2914 4964 6274 21 267 B 787 1577 3232 4356 16 091 19 805 C 1521 2666 3931 5771 7238 8781 D 738 1451 7733 10 543 13 630 18 020 Which element above has no p electrons in the valence shell? A Element A B Element B C Element C D Element D

5 [Turn Over 5. The diagram shows the structure of part of a crystal of ice. Which of the following is incorrect? A All bond angles surrounding each oxygen atom are 109.5. B Two electrons from each oxygen atom are involved in forming hydrogen bonds. C The hydrogen bonds are weaker than the O–H covalent bonds. D The open structure of ice causes ice to have a higher volume and lower density than water. 6. Which of the following has an exothermic enthalpy change? A Ba (g)  Ba+ (g) + e– B MgS (s)  Mg2+ (g) + S2– (g) C ½ N2 (g)  N (g) D F (g) + e–  F– (g)

6 [Turn Over 7. The value of pV RT is plotted against p at the same temperature for three gases – Ne, NH3 and C2H6, where p is the pressure and V is the volume of the gas. Which of the following correctly identifies the 3 gases? Gas 1 Gas 2 Gas 3 A NH3 C2H6 Ne B NH3 Ne C2H6 C Ne C2H6 NH3 D C2H6 Ne NH3

7 [Turn Over 8. Which graph would confirm that the rate of decomposition of ammonium chloride is a first order reaction? A B C D 0 [NH4Cl] time 0 rate of decomposition of NH4Cl [NH4Cl] 0 rate of decomposition of NH4Cl [NH4Cl] 0 [NH4Cl] time

8 [Turn Over 9. In an enzyme-catalysed reaction, the rate is affected by the concentration of substrate as shown in the graph below. The mechanism for the reaction is as shown: enzyme + substrate → enzyme-substrate complex (fast) enzyme-substrate complex → enzyme + product (slow) Which of the following is incorrect? A When [substrate] is low, the reaction is first order with respect to the substrate. B When [substrate] is high, the reaction is zero order with respect to the substrate. C The rate equation is given as: rate = k [enzyme-substrate complex]. D The reaction occurs in a two-step reaction.

9 [Turn Over 10. The equation for the Haber Process is shown below. Which of the following statements regarding the Haber Process is correct? A The use of Fe catalyst helps to lower the activation energy of the forward reaction more than that of the backward reaction. B The use of a higher pressure increases the equilibrium constant. C The rate constant of the backward reaction will decrease more than the rate constant of the forward reaction when temperature is decreased. D The rate constant of the backward reaction will decrease less than the rate constant of the forward reaction when temperature is increased. 11. A student carried out a titration involving 0.10 mol dm -3 Ba(OH)2 and 0.20 mol dm -3 HCOOH. Which of the following is a suitable indicator to indicate the end -point of this titration? A Phenolphthalein (pH range 8.2 – 10.0) B Methyl red (pH range 4.8 – 6.0) C Methyl orange (pH range 3.2 – 4.4) D There is no suitable indicator.

10 [Turn Over 12. Magnesium arsenate, Mg 3(AsO4)2, is a sparingly soluble salt commonly used to make insecticides. It dissociates in water according to the equation below. If the solubility product is S, what is the value of [AsO43– (aq)] at equilibrium? A S1/5 B ( 2 3S)1/5 C ( 2 5S)1/5 D ( 8 27S)1/5