MJC_H2_CHEM_P1_w_answers

1 Class Reg Number Candidate Name ____________________________ MERIDIAN JUNIOR COLLEGE JC 2 Preliminary Examination Higher 2 ____________________________________________________________________________ CHEMISTRY 9647/01 Paper 1 Multiple-Choice Questions 26 September 2014 1 hour Additional Materials: Data Booklet and OMR answer sheet ____________________________________________________________________________ INSTRUCTIONS TO CANDIDATES Write your name, class and register number in the spaces provided at the top of this page. There are forty questions in this sec tion. Answer all questions. For each question, there are four possible answers labelled A, B, C and D. Choose the one you consider correct and record your choice in soft pencil on the OMR answer sheet. Read very carefully the instructions on the OMR answer sheet. You are advised to fill in the OMR Answer Sheet as you go along; no additional time will be given for the transfer of answers once the examination has ended. This document consists of 16 printed pages (including 1 blank page). Use of OMR Answer Sheet Ensure you have written your name, class register number and class on the OMR Answer Sheet. Use a 2B pencil to shade your answers on the OMR sheet; erase any mistakes cleanly. Multiple shaded answers to a question will not be accepted. For shading of class register number on the OMR sheet, please follow the given examples: If your register number is 1, then shade 01 in the index number column. If your register number is 21, then shade 21 in the index number column. Calculator Model / No.

2 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 0.70 g impure sample of ammonium hydrogen sulfate, NH 4HSO4, is titrated with 0.200 mol dm–3 sodium hydroxide. 24.80 cm3 of aqueous sodium hydroxide is required for complete reaction. (Mr of NH4HSO4 = 115) What is the percentage purity of the sample? A 40.7% B 61.1% C 81.5% D 98.3% 2 20.00 cm 3 of 0.0200 mol dm –3 bromate(V), BrO3 –, was found to react completely with 80.00 cm3 of 0.0100 mol dm–3 hydroxylamine, NH2OH. BrO3 - ions are reduced as follows: BrO3 - + 6e + 6H+ → Br- + 3H2O Which of the following could be the half -equation for the oxidation of hydroxylamine ? A NH2OH → ½ N2O + 2H+ + ½ H2O + 2e B NH2OH + H2O → NO2 - + 5H+ + 4e C NH2OH → NO + 3H+ + 3e D NH2OH + 2H2O → NO3 - + 7H+ + 6e 3 Which of the particles would, on losing an electron, have a half -filled set of p orbitals? A N+ B O– C P– D Cl2+ 4 At 1.5 atm and 27 oC, 1 mole of gas E occupies a volume of 16.7 dm 3 while 1 mole of gas F occupies a volume of 2 0.0 dm3. Which one of the following gives a possible explanation for the observation? A Gas E could be He while gas F could be CO2. B Gas E could be N