JJC H2 Chem 2013 Prelim P1 QP

[Turn over JURONG JUNIOR COLLEGE 2013 JC 2 PRELIMINARY EXAMINATION Higher 2 CHEMISTRY 9647/01 Paper 1 Multiple Choice 19 September 2013 1 hour Candidates answer on separate paper. 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. Write your name, class and exam index number 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 or 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 on mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet. This document consists of 14 printed pages and 2 blank pages. 583

2 © Jurong Junior College 9647/01/PRELIM/2013 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 sample of cyclohexene is completely burnt in dry oxygen and the gaseous products are collected as shown. The increase in mass of the collecting vessels A and B of the apparatus are mA and mB respectively. What is the ratio of A B m m ? A 0.34 B 0.41 C 2.43 D 2.94 2. Some isotopes are unstable and undergo nuclear reactions. In one type of reaction, an unstable nucleus accepts an electron from an inner orbital of its electron cloud. The net effect is the conversion of a proton and an electron into a neutron. Which of the following describes this type of reaction? A 11C  12C B 111I  111Te C 76Br  75Br D 76Kr  75Br 3. Given the information: ∆H c(graphite) = –394 kJ mol–1 ∆Hf(H2O) = –286 kJ mol –1 ∆Hf(CH3OH) = –239 kJ mol –1 Which one of the following is the correct enthalpy change of combustion of methanol, CH 3OH, in kJ mol–1? A –441 B –727 C –919 D –1205 584

3 © Jurong Junior College 9647/01/PRELIM/2013 [Turn over 4. An experiment was conducted to determine the efficiency of the heating of a can of water using a spirit burner. The following data were recorded: Mass of ethanol burnt = m g Change in temperature of water = ∆T oC You are also given that: Relative molecular mass of ethanol = 46.0 Enthalpy change of combustion of ethanol = –1371 kJ mol −1 Specific heat capacity of water = c J g−1 K−1 Which expression below gives the efficiency of this heating process? A 1371 1000 100%300 T 46.0    m c B T4 6 . 0