JJC H2 Chem 2012 Prelim P1 QP

Jurong Junior College 9647/01/Prelim 2012 [Turn Over JURONG JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION Higher 2 CHEMISTRY 9647/01 Paper 1 Multiple Choice 13 September 2012 1 hour 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 shade your exam index number on the Answer Sheet in the spaces provided. There are forty questions on this paper. Answer all questions. For each que stion 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. A Data Booklet is provided. Do not write anything on the Data Booklet. This document consists of 16 printed pages.

2 Jurong Junior College 9647/01/Prelim 2012 [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. Use of the Data Booklet is relevant to this question. When x mol of cobalt is added to a solution containing y mol of cobalt(III) ions, cobalt (II) ions are formed in the resultant solution. In the resultant solution, the number of moles of cobalt(II) ions are three times that of cobalt(III) ions. Hence, which of the following are possible values of x and y? x y A 1 2 B 1 3 C 1 5 D 2 3 2. In an experiment, a sample of gadolinium element was vaporised, ionised and passed through an electric field. Analysis of the deflection occurring at the electric field region revealed the following data for a beam of 157Gd+. What would be the angle of deflection for a sample of doubly charged strontium ions? A 0.6° B 3.6° C 7.2° D 16.5° 3. In which pair of molecules is the strength of intermolecular forces of I greater than that of II? I II A CH3CH2CH2F CH3CH2CHF2 B trans CH3CCl=CClCH3 cis CH3CCl=CClCH3 C CH4 H2O D CH3CH2COOH CH3CH2CH2OH 2 o 157Gd+ Source  +

3 Jurong Junior College 9647/01/Prelim 2012 [Turn Over 4. The equation below represents the reaction of gaseous atoms of non -metal Y and of hydrogen to form gaseous Y2H6 molecules. 2Y(g) + 6H(g)  Y2H6(g) H = –2775 kJ mol1 The bond energy of an HY bond is 395 kJ mol1. What is the bond energy of a YY bond? A –405.0 kJ mol1 B –202.5 kJ mol1 C +202.5 kJ mol1 D +405.0 kJ mol1 5. Hydrogen peroxide slowly decomposes into water and oxygen. 2H2O2(l)  2H2O(l) + O2(g) Given that the standard enthalpy change of formation of H 2O2(l) is –188 kJ mol –1 and standard enthalpy change of formation of H 2O(l) is –286 kJ mol –1, calculate the enthalpy change of this decomposition. A −98 kJ mol–1 B −196 kJ mol–1 C +98 kJ mol–1 D +300 kJ mol–1 6. Nitrosyl chloride, NOCl, decomposes on heating according to the equation below: NOCl(g) ⇌ NO(g) + ½ C