IJC_H2_CHEM_P3

INNOVA JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION 2 in preparation for General Certificate of Education Advanced Level Higher 2 CANDIDATE NAME CLASS INDEX NUMBER CHEMISTRY Paper 3 Free Response Candidates answer on separate paper. Additional Materials: Writing Papers Data booklet 9746/03 17 September 2009 2 hours READ THESE INSTRUCTIONS FIRST Write your name and class on all the work you hand in. Write in dark blue or black pen on both sides of the paper. You may use a soft pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer 4 out of 5 questions. You are advised to show all working in calculations. You are reminded of the need for good English and clear presentation in your answers. You are reminded of the need for good handwriting. Your final answers should be in 3 significant figures. At the end of the examination, fasten all your work securely together. The number of marks is given in the brackets [ ] at the end of each question or part question. This document consists of 11 printed pages and 1 blank page. Innova Junior College [Turn over

PRELIM 2  INNOVA 9746/03/09 [Turn over 2 Answer 4 out of 5 questions 1 (a) Compound A reacts with bromine to form compound B as follows. Describe the mechanism for this reaction, including curly arrows showing the movement of electrons, and all charges. [3] (b) The following table gives the boiling points and relative molecular masses for four organic compounds. Compound Formula Mr b.p. / °C C NH2CH2CH2COOH 89 235 D HOCH2CH2COOH 90 75 E CH3CH2CH2CH2CH3 72 36 F (CH3)4C 72 10 By comparing C with D and E with F , suggest explanations for the similarities or differences in the boiling points within each of these two pairs. [4] (c) (i) When barium peroxide, BaO 2 is added to water, barium hydroxide and compound G are formed. When the solution is acidified, and added to potassium manganate solution, a colourless solution is formed. Identify compound G. Write down the equation of barium peroxide with water and explain the observation. (ii) Explain whether barium nitrate or calcium nitrate will be more thermally stable under strong heat. [4] (d) The standard reduction potential for the following reaction is +0.20 V. 2HCO 2 – (aq) + 2CO2 (g) + 6H+ (aq) + 6e  C4H4O6 2– (aq) + 2H2O (l) Using relevant information in the Data Booklet, calculate the E θ cell for the reaction when hydrogen peroxide solution is added to an acid solution containing C