BMSS Prelim P2

Class Index Number Name BUKIT MERAH SECONDARY SCHOOL PRELIMINARY EXAMINATION 2024 SECONDARY 4 EXPRESS 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 and name 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. 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 26. The use of an approved scientific calculator is expected, where appropriate. This document consists of 26 printed pages. Setter: Ms Jacqueline How [Turn over

2 JH/BMSS/2024/4EXP/PRELIM/6092/02 [Turn over Section A Answer all questions. 1 A list of compounds is shown. aluminium oxide calcium bromide calcium oxide ethane ethene hydrogen chloride methane nitrogen dioxide potassium iodide potassium manganate(VII) sodium chloride Answer the following questions using only the compounds in the list. Each compound may be used once, more than once or not at all. Which compound (a) when in acidified solution, is used to test for sulfur dioxide, ……………………………………………………………………………………………………………[1] (b) is the main constituent of natural gas, ……………………………………………………………………………………………………………[1] (c) when dissolved in water, gives a yellow precipitate on addition of acidified aqueous silver nitrate, ……………………………………………………………………………………………………………[1] (d) is used in industries to neutralise acidic gases, ……………………………………………………………………………………………………………[1] (e) is a reactant used in the manufacture of ethanol, ……………………………………………………………………………………………………………[1] (f) reacts with both nitric acid and potassium hydroxide to give salt and water? ……………………………………………………………………………………………………………[1] [Total: 6]

3 JH/BMSS/2024/4EXP/PRELIM/6092/02 [Turn over 2 A sample of ink contains a mixture of red, blue and yellow dyes. The chromatograms are run using a mixture of ethanol and water as solvent. Fig. 2.1 shows the graphical results of the coloured dyes of different Rf values in solvents with different proportions of ethanol. Fig. 2.1 (a) From Fig 2.1, deduce the Rf values of the blue dye on the chromatogram when the solvent is a mixture of 60cm3 of ethanol and 40cm3 of water. ……………………………………………………………………………………………………………[1] (b) The chromatography process is repeated with a filter paper when the solvent is a mixture of 20 cm3 of ethanol and 80 cm3 of water. A sample of ink was added to the middle of the filter paper. On Fig. 2.2, sketch the chromatogram results for the three coloured inks. Label your results clearly. Fig. 2.2 [2] (c) The st