2022 BtySS Chem Prelims P2

BEATTY SECONDARY SCHOOL PRELIMINARY EXAMINATION 2022 SECONDARY FOUR EXPRESS CANDIDATE NAME CLASS REGISTER NUMBER CHEMISTRY 6092/02 Paper 2 19 August 2022 Setter: Mr Yeo Chee Keong 1 hour 45 minutes Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name, class and register number on all the work you hand in. Write in dark blue or black pen. You may use an HB pencil for any diagrams or graphs. 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. A copy of the Periodic Table is printed on page 20. For Examiner’s Use A 50 B7 12 B8 8 B9… 10 Total 80 The use of an approved scientific calculator is expected, where appropriate. This document consists of 20 printed pages and 0 blank page. [Turn over

2 Section A Answer all questions in this section in the spaces provided. The total mark for this section is 50. A1 Use the list of substances to answer the questions. You may use each substance once, more than once or not at all. iodine ozone dichloroethane magnesium potassium manganate(VII) copper(II) sulfate calcium chloride diamond (a) Which substance is a good reducing agent? ………………………………………………………………………………………… [1] (b) Which substance can be formed under ultraviolet radiation conditions? ………………………………………………………………………………………… [1] (c) Which substance exists as three different colours when the physical state is changed? ………………………………………………………………………………………… [1] (d) Which two substances can react to undergo a redox reaction? ………………………………………………………………………………………… [1] (e) Which substances are elements? ………………………………………………………………………………………… [1] [Total: 5]

3 A2 Lithium is a metal with low melting point and low density. It can react with cold water to form lithium hydroxide and hydrogen gas. (a) Write a chemical equation for the reaction of lithium with cold water. ………………………………………………………………………………………… [1] (b) Given that 0.2 g of lithium metal was used in the reaction with an excess of cold water, determine the volume of hydrogen gas produced. [2] (c) Describe how you can determine that the reaction has reached completion. ………………………………………………………………………………………………. ………………………………………………………………………………………… [1] [Total: 4] A3 Hydrochloric acid reacts with methanol to form chloromethane and water in the equation as shown. HCl(aq) + CH3OH(aq) → CH3Cl(g) + H2O(l) (a) Briefly describe a practical method by which the concen