LVSS PRELIM 2023 4NA SCI CHEM P4

LOYANG VIEW SECONDARY SCHOOL Preliminary Examination 2023 Secondary Four Normal (Academic) CANDIDATE NAME : ……………………………………………………………….......... CLASS : …………………. INDEX NUMBER : ……………. SCIENCE (CHEMISTRY) 5105/04 Paper 4 3 Aug 2023 Papers 3 and 4: 1 hour 15 minutes Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name, class and index number on all the work you hand in. Write in dark blue or black pen on both sides of the paper. You may use an HB pencil for any diagrams or graphs. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions in Section A and any two questions in Section B. The use of an approved scientific calculator is expected, where appropriate. In calculations, you should show all the steps in your working, giving your answer at each stage. You are advised to spend no more than 30 minutes on Paper 3. You may proceed to answer Paper 4 as soon as you have completed Paper 3. A copy of the Periodic Table is printed on page 11. At the end of the examination hand in your answers to Paper 3 and Paper 4 separately. The number of marks is given in brackets [ ] at the end of each question or part question. Setter: Mdm Elvina Abu Hasan For Examiner’s Use Section A / 14 Section B / 16 Total / 30 This paper consists of 11 printed pages.

2 Section A Answer all the questions in the spaces provided. 1 The positions of 8 elements in the Periodic Table are shown in Fig. 1.1. The letters A to H do not represent the chemical symbols of the elements. Fig. 1.1 (a) Which element, A to H, forms an ion with a charge of +2? ……………………………………………………………………………………......[1] (b) Explain why element H is unreactive? ……………………………………………………………………………………......[1] (c) An atom of element X has an electronic structure of 2,7. Which element, A to H, will have properties most similar to X? ………………………………………………………………………………...…….. [1] [Total: 3] 2 Reacting an acid with a base is a common method of preparing salts. This is known as an acid-base reaction. Table 2.1 gives details of three salts that can be prepared by acid-base reactions. Table 2.1 salt formula relative formula mass, Mr copper(II) sulfate CuSO4 160 magnesium nitrate Mg(NO3)2 sodium sulfate Na2SO4 (a) Use data from the Periodic Table to complete Table 2.1 by calculating the relative formula mass, Mr, of magnesium nitrate and sodium sulfate. [2]

3 (b) Calculate the mass of 0.5 mol of magnesium nitrate, Mg(NO3)2. mass of magnesium nitrate = ……………………….. g [1] (c) (i) Identify the acid and base required to produce sodium sulfate. acid ………………………………………………………….. base .………………………