MJC_H1_CHEM_P1_W_ANS

Name: _____________________ Class: ________ Reg Number: _____ MERIDIAN JUNIOR COLLEGE JC2 Preliminary Examination Higher 1 ___________________________________________________________________ CHEMISTRY 8872 / 01 Paper 1 Multiple Choice 23 September 2011 50 minutes Additional Materials: Multiple Choice Answer Sheet Data Booklet ___________________________________________________________________ READ THESE INSTRUCTIONS FIRST Write your name, class and register number in the spaces at the top of this page. Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. There are thirty 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. This document consists of 13 printed pages (excluding this cover page). Use of 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.

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[Turn Over 1 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 10 cm 3 sample of ethanethiol, CH 3CH2SH, was exploded with 80 cm 3 of oxygen according to the given equation: CH3CH2SH + 9 2 O2  2 CO2 + SO2 + 3 H2O The resultant gas mixture was c ooled to room temperature and passed through aqueous sodium hydroxide. Wh at would be the final volume of gas(es) in the resultant mixture? A 10 cm 3 B 35 cm 3 C 45 cm 3 D 75 cm 3 2 When hydrogen peroxide is added to acidified potassium dichromate( VI), the reaction that occurs is: Cr2O7 2- + 3H2O2 + 8H+  2Cr3+ + 3O2 + 7H2O Which of the following statements is incorrect for this reaction? A The colour changes from orange to green. B The hydrogen peroxide acts as a reducing agent. C The oxidation number of oxygen does not change. D There is bubbling observed as the reaction proceeds.

[Turn Over 2 3 Which pair of species exhibit identical deflections in an electric field? A 14N+ and 14N- B 14N+ and 28Si2+ C 16O2- and 4He2+ D 16O2- and 32S2- 4 Which of the following pairs of subst ances have the same types of structure an