SJI 2022 Y4 Prelim Chemistry 6092 P2 QP

ST JOSEPH’S INSTITUTION PRELIMINARY EXAMINATION 2022 (YEAR 4) CANDIDATE NAME CLASS INDEX NUMBER CHEMISTRY Paper 2 Candidates answer on the Question Paper. No Additional Materials are required. 6092/02 19 August 2022 1 hour 45 minutes (10:40 – 12:25) READ THESE INSTRUCTIONS FIRST Write your name, class and index number on all the work you hand in. Write in dark blue or black fluid ink pen. You may use a soft pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, glue or correction fluid. Section A Answer all questions in the spaces provided. Section B Answer all three questions. The last question is in the form either/or. Answer all questions in the spaces provided. The number of marks is given in brackets [ ] at the end of each question or part question. The use of an approved scientific calculator is expected, where appropriate. A copy of the Periodic Table is printed on page 2. For Examiner’s Use Section A / 50 Section B / 30 Total / 80 This document consists of 22 printed pages including this cover page.

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3 Section A (50 marks) Answer all questions in this section in the spaces provided. A1 Study the flowchart below and answer the following questions. (a) Identify substances W, X and Y. W: ………………………………………………………….. X: …………………………………………………………... Y: ……………………………………………………….….. [3] (b) Describe a chemical test to confirm the identity of the colourless gas Z. ..………………..…………………………………………………………………………… ………………….………………………………………………………………………..[1] [Total: 4] add aqueous ammonia dropwise then in excess green solution colourless gas Z + mixture of white and green precipitate formed but white precipitate subsequently dissolved add dilute sulfuric acid white precipitate Y formed metal W and colourless solution X filter mixture and add acidified aqueous barium nitrate to filtrate

4 A2 Silicon t etrachloride, SiCl4, and ethoxyethane, (C 2H5)2O, are both liquids at roo m temperature and pressure. An experiment is performed to react silicon tetrachloride with ethoxyethane to produce two oxochlorides, Si2OCl6 and Si3O2Cl8. (a) (i) The temperature of the experiment is increased. State the effect of increasing temperature on the rate of reaction. Explain your answer in terms of reacting particles. ……………..………………………………………………………………………… ……………..………………………………………………………………………… ……………..………………………………………………………………………… ……………..………………………………………………………………………… ……………..………………………………………………………………………… ………………..……………………................................................................[