2022 HIHS Chem Prelims P2

1 HOLY INNOCENTS’ HIGH SCHOOL Candidate Name Class Index Number PRELIMINARY EXAMINATION 2022 SECONDARY 4 EXPRESS CHEMISTRY Paper 2 6092/02 Date: 17 Aug 2022 Duration: 1 h 45 min Additional Materials: NIL READ THESE INSTRUCTIONS FIRST Write your name, class and index number on all the work you hand in. Write in dark blue or black pen. You may use an HB pencil for any diagrams or graphs. Do not use paper clips, glue or correction tape/fluid. Section A Answer all questions. Write your answers in the spaces provided on the question paper. Section B Answer all three questions, the last question is in the form either/or. Write your answers in the spaces provided. Information for Candidates A copy of the Periodic Table is printed on page 2. You are advised to spend no longer than 65 minutes on Section A and no longer than 40 minutes on Section B. For Sections A and B, the number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s use Sect A Sect B ……… ……… ……… Total Set by: Mr Daniel Lau Vetted by: Ms Woo Wei Shan This document consists of 21 printed pages (including cover page). O 80

2 The Periodic Table of the Elements Group I II III IV V VI VII 0 key 1 H hydrogen 1 2 He helium 4 3 Li lithium 7 4 Be beryllium 9 proton (atomic) number atomic symbol name relative atomic mass 5 B boron 11 6 C carbon 12 7 N nitrogen 14 8 O oxygen 16 9 F fluorine 19 10 Ne neon 20 11 Na sodium 23 12 Mg magnesium 24 13 Al aluminium 27 14 Si silicon 28 15 P phosphorus 31 16 S sulfur 32 17 Cl chlorine 35.5 18 Ar argon 40 19 K potassium 39 20 Ca calcium 40 21 Sc scandium 45 22 Ti titanium 48 23 V vanadium 51 24 Cr chromium 52 25 Mn manganese 55 26 Fe iron 56 27 Co cobalt 59 28 Ni nickel 59 29 Cu copper 64 30 Zn zinc 65 31 Ga gallium 70 32 Ge germanium 73 33 As arsenic 75 34 Se selenium 79 35 Br bromine 80 36 Kr krypton 84 37 Rb rubidium 85 38 Sr strontium 88 39 Y yitrium 89 40 Zr zirconium 91 41 Nb niobium 93 42 Mo molybdenum 96 43 Tc technetium - 44 Ru ruthenium 101 45 Rh rhodium 103 46 Pd palladium 106 47 Ag silver 108 48 Cd cadmium 112 49 In indium 115 50 Sn tin 119 51 Sb antimony 122 52 Te tellurium 128 53 I iodine 127 54 Xe xenon 131 55 Cs caesium 133 56 Ba barium 137 57 – 71 lanthanoids 72 Hf hafnium 178 73 Ta tantalum 181 74 W tungsten 184 75 Re rhenium 186 76 Os osmium 190 77 Ir iridium 192 78 Pt platinum 195 79 Au gold 197 80 Hg mercury 201 81 Tl thallium 204 82 Pb lead 207 83 Bi bismuth 209 84 Po polonium - 85 At astatine - 86 Rn radon - 87 Fr francium - 88 Ra radium - 89 - 103 actinoids 104 Rf Rutherfordium - 105 Db dubnium - 106 Sg seaborgium - 107 Bh bohrium - 108 Hs hassium - 109 Mt meitnerium - 110 Ds darmstadtium - 111 Rg roentgenium - 112 Cn copernicium - 114 Fl flerovium - 116 Lv livermorium - 57 La lanthanum 139 58 Ce cerium 140 59 Pr praseodymium 141 60 Nd neodymium 144 61 Pm promethium - 62 Sm samarium 150 63 Eu europium 152 64 Gd gadolinium 157 65 Tb terbium 159 66 Dy dysprosium 163 67 Ho holmium 165 68 Er erbium 167 69 Tm thulium 169 70 Yb ytterbium 173 71 Lu lutetium 175 89 Ac actinium - 90 Th thorium 232 91 Pa protactinium 231 92 U uranium 238 93 Np neptunium - 94 Pu plutonium - 95 Am americium - 96 Cm curium - 97 Bk berkelium - 98 Cf californium - 99 Es einsteinium - 100 Fm fermium - 101 Md mendelevium - 102 No nobelium - 103 Lr lawrencium - The volume of one mole of any gas is 24 dm3 at room temperature and pressure (r.t.p.) lanthanoids actinoids

3 Section A [50 marks] Answer all questions in this section. Write your answer in the spaces provided. A1 Fig. A1.1 shows part of the Periodic Table. Fig. A1.1 Answer the following questions using only the symbols of the elements in Fig. A1.1. Each symbol may be used once, more than once or not at all. Give the symbol of an element that: (a) is used as a catalyst for the Haber process. ………………………………………………………………………………………….. [ 1] (b) is used as a catalyst in a catalytic converter. ………………………………………………………………………………………….. [1] (c) is used to galvanise iron. ………………………………………………………………………………………….. [1] (d) is used to define the relative atomic mass of elements. ………………………………………………………………………………………….. [1] (e) forms an oxide which contributes to acid rain. ………………………………………………………………………………………….. [1] (f) reacts with cold water to form a solution that turns Universal indicator violet. ………………………………………………………………………………………….. [1] [Total: 6]

4 A2 The following question is about bromine and compounds containing bromine. (a) Bromine is a liquid. Describe the arrangement and motion of the molecules in bromine liquid. …………………………………………………………………………………………....... …………………………………………………………………………………………....... ………………………………………………………………………………………….. [2] (b) Draw the dot and cross diagram of a bromine molecule, showing only the valence electrons. [1] (c) Briefly explain why reddish -brown bromine liquid will turn colourless when it is added to an aqueous solution of potassium iodide. Include an ionic equation to support your explanation. …………………………………………………………………………………………....... …………………………………………………………………………………………....... …………………………………………………………………………………………....... …………………………………………………………………………………………....... ………………………………………………………………………………………….. [3] [Total: 6]

5 A3 A student carried out some experiments to investigate the displacement reactions of four metals namely, copper, cobalt, iron and a metal E. She added the metals separately to various salt solutions.and the observations are recorded in Table A3.1 below. metal salt solutions copper(II) sulfate cobalt(II) sulfate iron(II) sulfate E2SO4 copper no change, solution remains green no change, solution remains colourless cobalt brown solid forms in pink solution no change, solution remains green no change, solution remains colourless iron brown solid forms in green solution no change, solution remains colourless E brown solid forms in colourless solution grey solid forms in colourless solution grey solid forms in colourless solution Table A3.1 (a) It was concluded that the order of reactivity of the four metals, in increasing order is copper, cobalt, iron, E. Fill in the blanks in Table A3.1 by deducing the observations of the reactions between (i) copper and cobalt(II) sulfate solution, and (ii) iron and cobalt(II) sulfate solution [2] (b) Write a balanced chemical equation for the reaction between copper(II) oxide and metal E. ………………………………………………………………………………………….. [2] (c) Given that magnesium is found between iron and E in the reactivity series, suggest the method of extraction for metal E from ores. ………………………………………………………………………………………….. [1] [Total: 5]

6 A4 The Andrussow process is an industrial process for the production of hydrogen cyanide in the presence of platinum as a catalyst. The structural formulae of all chemicals are shown in the chemical equation below: Table A4.1 shows some information about the bonds present in the chemicals. bond bond energy / kJmol-1 bond bond energy / kJmol-1 H – N 390 C – H 413 H – O 464 O = O 498 C { N 891 Table A4.1 (a) Using the information from Table A4.1, explain w hy the enth