MSHS 2024 Chem Prelim Paper 2

Class/ Index Number / Centre Number/ ‘O’ Level Index Number / Name MARIS STELLA HIGH SCHOOL PRELIMINARY EXAMINATION SECONDARY FOUR CHEMISTRY 6092/02 Paper 2 15 August 2024 1 hour 45 minutes Candidates answer on the Question Paper. No additional materials are required. READ THESE INSTRUCTIONS FIRST Write your class, index number, Centre number, O level index number and name in the spaces at the top of this page. 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. Write your answers in the spaces provided. Section B Answer one question. Write your answers 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 24. The use of an approved scientific calculator is expected, where appropriate. For Examiner’s Use Section A Section B Total This document consists of 24 printed pages. 70 10 80

2 Section A Answer all questions in this section in the spaces provided. The total mark for this section is 70. 1 The position of seven elements from Period 1 to 4 of the Periodic Table is represented by letters A, B, C, D, E, F and G as shown below. The letters do not represent the chemical symbols of the elements. A D F G B C E Use the letters, A to G, to answer the following questions. They can be used once, more than once, or not at all. (a) Which element contains the smallest number of protons in each atom? …………………………………………………………………………………………….............[1] (b) Which element combines with element F to form a compound which has a low boiling point? …………………………………………………………………………………………….............[1] (c) Which element is the strongest reducing agent? …………………………………………………………………………………………….............[1] (d) Which element has common oxidation states of +2, +4, +6 and +7? …………………………………………………………………………………………….............[1] (e) Which element is important in providing an inert atmosphere for reactions? …………………………………………………………………………………………….............[1] [Total: 5]

3 2 A student investigated the change in mass when hydrated cobalt chloride was heated. The word equation for the reaction is shown below: hydrated cobalt chloride → anhydrous cobalt chloride + water 2.0 g of hydrated cobalt chloride was heated in a test-tube gently for 30 seconds. The test-tube and its contents was cooled and the mass of the test-tube and contents was measured. The experiment was repeated until the mass of the test-tube and contents does not change. (a) Explain why the mass of the test-tube and contents decreased. ……………………………………………………………………………………………………..[1] (b) Suggest