Yuan Ching Prelim P2

1 YUAN CHING SECONDARY SCHOOL Secondary Four Express Course Preliminary Examination 2024 CANDIDATE NAME CLASS INDEX NUMBER CHEMISTRY 6092/02 Paper 2 23 Aug 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 and name on all the work you hand in. Write in dark blue or black pen. You may use an HB soft pencil for any diagrams or graphs. Do not use staples, paper clips, highlighters, glue or correction fluid. Section A (70 marks) Answer all questions. Write your answers in the spaces provided. Section B (10 marks) 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 can be found on Page 26. The use of a scientific calculator is expected, where appropriate. For Examiner’s Use Section A Section B 11: 12: Total / 80 This paper consists of 26 printed pages.

2 Section A [70 marks] Answer all the questions in this section. Write your answers in the spaces provided on the question paper. 1 Choose from the following compounds in Fig. 1.1 to answer the questions. Fig. 1.1 Each compound, A, B, C, D, E and F may be used once, more than once or not at all. State which compound: (a) has a molecule with only 11 atoms [1] (b) is oxidised to form ethanoic acid [1] (c) is an isomer of butene [1] (d) reacts with hydrogen in the presence of a catalyst to make an alkane [1] [Total: 4]

3 2 An experiment in Fig. 2.1 was set up for measuring the rates of diffusion of gases. The time taken for 100 cm3 of some gases at room temperature and pressure to diffuse from this apparatus are shown in the Table 2.1. Table 2.1 gas tested time /s carbon monoxide, CO 132 chlorine, Cl2 211 methane, CH4 100 nitrogen, N2 ? oxygen 141 Fig. 2.1 (a) Name and explain the gas that diffused fastest. [1] (b) Explain in terms of kinetic particle theory why the temperature must be kept constant in this experiment. [2] (c) Suggest the time that 100 cm3 of nitrogen would take to diffuse out of the apparatus. [1] (d) Explain why this apparatus is unsuitable for finding the rate of diffusion for ammonia gas. [1] [Total: 5]

4 3 Table 3.1 shows results of different tests conducted to compare the properties of two dibasic acid, sulfuric acid and tartaric acid, of the same concentration. Table 3.1 acid X Y Universal Indicator red orange volume of gas collected 10 s after reacting with magnesium 14 cm3 6 cm 3 volume of sodium hydroxid