2024 TMJC JC2 H2 Chemistry - Prelim P4 (QP)

1 CANDIDATE NAME CIVICS GROUP H2 CHEMISTRY 9729/04 Paper 4 Practical 27 August 2024 2 hours 30 minutes Candidates answer on the Question Paper. This document consists of 23 printed pages and 1 blank page. READ THESE INSTRUCTIONS FIRST Write your name and Civics Group in the spaces at the top of the page. Give details of the practical shift and laboratory where appropriate, in the boxes provided. 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. Answer all questions in the spaces provided on the question paper. The use of an approved calculator is expected, where appropriate. You may lose marks if you do not show your working or if you do not use appropriate units. Qualitative Analysis Notes are printed on pages 23 and 24. The number of marks is given in brackets [ ] at the end of each question or part question. Shift Laboratory For Examiner’s Use 1 / 18 2 / 15 3 / 13 4 / 9 Total / 55 TAMPINES MERIDIAN JUNIOR COLLEGE JC2 PRELIMINARY EXAMINATION

2 Tampines Meridian Junior College 2024 JC2 Preliminary Examination H2 Chemistry Answer all questions in the spaces provided. 1 Investigation of some inorganic and organic reactions In this question, you will be investigating some inorganic and organic reactions by carrying out the stipulated tests. Carefully record your observations in Tables 1.1 and 1.2. Unless otherwise stated, the volumes given below are approximate and should be estimated rather than measured. (a) Organic analysis In this question, you will deduce the structure of an organic compound, FA 1. FA 1 has the molecular formula C4H8O2 with two functional groups present. Do not carry out the tests for which observations have been recorded. Do not use the Bunsen burner for heating in this part of the question. Instead, use the hot water provided. Table 1.1 tests observations (i) Place about 2 cm depth of aqueous sulfuric acid in a test-tube. To this test -tube, add about 1 cm depth of FA 1, followed by 1 drop of aqueous potassium manganate(VII). Warm the mixture in the hot water bath for two minutes. (ii) Add 1 cm depth of aqueous silver nitrate to a test-tube. Then slowly add 1 cm depth of aqueous sodium hydroxide. Add aqueous ammonia slowly, with shaking, until the precipitate just dissolves. To this mixture, add about 1 cm depth of FA 1. Place the test-tube containing the mixture in the water bath for two minutes. (iii) Place about 1 cm depth of FA 1 in a test -tube. To this test -tube, add 2,4 -dinitrophenylhydrazine dropwise. Orange ppt. formed (iv) Place about 1 cm depth of FA 1 and add 8 drops of aqueous sodium hydroxide in a test -tube. Then, add aqueous iodine dropwise, until a permanent yellow / orange colour is obtained.