IJC_2008_H2 Chemistry_Prelim II_Paper3

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 Graph Paper Data booklet 9746/03 09 September 2008 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 10 printed pages and 0 blank page. Innova Junior College [Turn over

2 Answer 4 out of 5 questions 1 The colours of various vanadium ions are given in the table below. Oxi van V IV III II dation Number of adiuim ions Colour Yellow Blue Gre Violet en (a) Use Eθ values from the Data Booklet, predict what colour changes will be observed when copper is added separately and in excess to ammonium vanadate(V), NH 4VO3(aq), acidified with dilute sulfuric( VI) acid. Write balanced equation(s) for the reaction(s) you predict will occur. [3] (b) Anhydrous copper sulfate, CuSO 4(s), is a white powder that readily dissolves in water. (i) Describe and explain using balanced equations, what is seen when CuSO 4(s) is stirred with water. (ii) Describe and explain the final colour change seen when an excess of NH 3(aq) is added to CuSO4(aq). [4] (c) Hot ethanolic KOH C 6H5CH2Cl C 7H8O + C6H5CH2OCH2CH3 F G H (i) Suggest an identity for compound G. (ii) The hydroxide ion and ethanol can take part in an acid-base reaction. Write an equation to represent this. (iii) Compound F undergo nucleophilic substitution reactions with different nucleophiles to form compound G and H respectively. Identify the two nucleophiles in the reactions. (iv) Suggest a simple chemical test by which compound F and bromobenzene can be distinguished from each other. [5] (d) Step I KCN heat with H 2SO4(aq) (CH3)2CHOH (CH 3)2CHBr K L In ethanol followed by ethanol, Conc H 2SO4 and heat (i) State the reagents and c