ACJC Prelim 2016 (all papers & soln)

1 © ACJC 2016 9647/01/Prelim/2016 [Turn over CHEMISTRY Preliminary Examination CHEMISTRY 9647/01 Higher 2 Paper 1 Multiple Choice 29 August 2016 1 hour Additional Materials: Multiple Choice Answer She et Data Booklet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluids. Write your name, index number and tutorial class on the Answer Sheet in the spaces provided unless this has been done for you. 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 Answer Sheet. Read the instructions on the Answer Sheet very carefully. 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. The use of an approved scientific calculator is expected, where appropriate. This document consists of 17 printed pages and 1 blank page. 9647/01/Prelim/16 2016 [Turn over 1

2 9647/01/Prelim/2016 [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 3.00 g of an impure sample of calcium carbonate was heated strongly until there was no change in mass. 200 cm3 of carbon dioxide, measured at room conditions, was obtained. What is the percentage purity of calcium carbonate? A 27.8 % B 29.8 % C 30.4 % D 35.8 % 2 Use of the Data Booklet is relevant to this question. Which underlined element in the following species has the +6 oxidation number? A ReOCl4 B H2P2O72– C TiCl4 D SbCl52– 3 Use of the Data Booklet is relevant to this question. Deuterium, D1 2 , is an isotope of hydrogen. Which of the following species has more electrons than protons, and more neutrons than protons? A D3O+ B ND4+ C OD– D AlD4– 4 In which of the following pairs does the first compound have a higher melting point than the second compound? first compound second compound A Mg3N2 Al2O3 B NH2OH H2O C CH3OCH3 (CH3)2NH D 2

3 9647/01/Prelim/2016 [Turn over 5 Which of the following bonds is not present in the following molecule? escitalopram A a σ bond formed by sp3–sp2 overlap between two C atoms B a σ bond formed by sp–sp overlap between C and N atoms C a σ bond formed by sp2–sp2 overlap between two C atoms D a σ bond formed by sp3–sp2 overlap between C and N atoms 6 Which of the following sets of compounds and ions is arranged in increasing bond angles? A NO2+ < CO32– < SO42– B IF4– < N2O4 < N3– C ICl2– < H2S < NO2 D SCl2 < C2H2 < CH2Cl2 7 0.50 g of a volatile liquid was placed in a syringe with a frictionless piston. The syringe was slowly warmed up till 91.0 oC at atmospheric pressure. The volume occupied in the syringe was 200.0 cm3 when all the liquid was vaporised. Assuming the vapour behaves as an ideal gas, what is the relative mo