2023 HYSS Prelim ScChem 4NA P4

Name: Index Number: Class: HUA YI SECONDARY SCHOOL Preliminary Examination Paper 3 & 4: 1 hour 15 minutes Candidates answer on the Question Paper provided. Additional Materials: Nil READ THESE INSTRUCTIONS FIRST Write your Name, Index Number and Class at the top of this page. Write in dark blue or black pen. You may use a soft pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Section A Answer all questions. Write your answers in the spaces provided on the question paper. Section B Answer any two questions. Candidates are reminded that all quantitative answers should include appropriate units. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. A copy of the Periodic Table is provided on page 12. This document consists of 12 printed pages including the cover page. © HYSS 2023 No part of this document may be reproduced in any form or transmitted in any form or by any means without the prior permission of Hua Yi Secondary School. [Turn Over 4NA 4NA For Examiner’s Use Section A Section B TOTAL SCIENCE (CHEMISTRY) 5105/04 5107/04 Paper 4 2 August 2023

2 Sec 4NA Science (Chemistry) P4 Preliminary Examination Hua Yi Secondary School Section A (14 marks) Answer all questions in the spaces provided. 1 A new food item, X, was tested for a banned food dye. A sample of the food item was dissolved in a suitable solvent and the resulting solution was separated on a piece of chromatography paper, together with solutions of five known food dyes (E120, E121, E140, E150 and E160a). Dye with the number code E121 is banned. The diagram shows the chromatogram obtained. (a) Identify all the food dyes present in the candy. …………………………………………………………………………………………………. [1] (b) Explain why E121 moves further up the chromatography paper than E120. …………………………………………………………………………………………………. [1] (c) Explain why the start line should be drawn with a pencil and not a pen. …………………………………………………………………………………………………. …………………………………………………………………………………………………. [1] X E120 E121 E140 E150 E160a solvent front start line

3 Sec 4NA Science (Chemistry) P4 Preliminary Examination Hua Yi Secondary School 2 The table shows some information about four particles A, B, C and D. (The letters do not represent the chemical symbols of any element.) particle number of protons number of neutrons mass number electronic configuration A 6 6 2, 4 B 15 31 C 6 8 14 2, 4 D 12 23 2, 8, 1 (a) Complete the table by filling in the missing information. [3] (b) Which two particles are isotopes of the same element? …………………………………………… and ……………………………………….……… [1] (c) Deduce the identity of particle C. ………………………………………………………………………………………………..… [1] 3 The table gives details of two salts that are found in daily life. salt formula relative formula mass, Mr iron(II) nitrate Fe(NO3)2 calcium carbonate 100 [2] (a) Complete the table by filling the missing details. (b) Calculate the mass, in grams, of 0.2 mole of calcium carbonate. [relative atomic masses, Ar : C, 12; Ca, 40; O, 16] mass of calcium carbonate = …………… g [1]

4 Sec 4NA Science (Chemistry) P4 Preliminary Examination Hua Yi Secondary School 4 In the extraction of iron, limestone is placed into the blast furnace together with two other raw materials. (a) Name the two other raw materials required for the extraction of iron. …………………………………….....…and ………………………………………………… [1] (b) Explain why limestone is added to the blast furnace. …………………………………………………………………………………..……………… [1] (c) Iron is produced from the reduction of its ore by carbon monoxide. Balance the following equation. ……..Fe2O3 (s) + ..……CO (g) → .……Fe (s) + ..……CO 2 (g) [1]

5 Sec 4NA Science (Chemistry) P4 Preliminary Examination Hua Yi Secondary School Section B (16 marks) Answer any two questions from this section in the spaces provided. 5 The observation for the reactions of four metals, W, X, Y and Z with steam and acid are shown in the table. experiments metal S T U X reaction with steam very bright flame observed no visible reaction metal burns in steam metal glows faintly reaction with acid vigorous effervescence no visible reaction rapid bubbling observed some bubbling observed (a) (i) Arrange the four metals in order of their reactivity, starting with the most reactive metal. most reactive least reactive [1] (ii) Suggest how metal S can be extracted from its oxide. …………………………………………………………………………………….. [1] (iii) Write a balanced equation for the reaction between zinc and steam. …………………………………………………………………………………….. [1]

6 Sec 4NA Science (Chemistry) P4 Preliminary Examination Hua Yi Secondary School (b) Part of the reactivity series for metals is shown below. sodium most reactive calcium magnesium zinc iron lead copper least reactive The following list shows how long ago these metals were discovered. calcium 206 years ago copper 7000 years ago iron 3000 years ago lead 7000 years ago magnesium 259 years ago sodium 207 years ago zinc 2000 years ago Explain why some metals were discovered much earlier than others. …………………………………………………………………………………..………... …………………………………………………………………………………..………... …………………………………………………………………………………..………... …………………………………………………………………………………..………... [2]

7 Sec 4NA Science (Chemistry) P4 Preliminary Examination Hua Yi Secondary School (c) The table shows the atomic number and melting points of some metals. atomic number melting point / ºC 3 180 11 96 19 ? 37 36 55 28 (i) Plot a graph of melting point against the atomic number. Mark each point with a cross (×). Draw a curved line of best fit through your plotted points. atomic number [2] (ii) From your graph determine the melting point of the metal with an atomic number of 19. melting point = ………… ºC [1] 0 10 20 30 40 50 60 200 160 120 40 80 0 melting point / °C

8 Sec 4NA Science (Chemistry) P4 Preliminary Examination Hua Yi Secondary School 6 A section of the Periodic Table with seven labelled elements is given. The letter labels, P, Q, R, W, U, Y and Z, are not the chemical symbol of the elements. P Z W Y U Q R Use the letters P, Q, R, U, W, Y and Z in the diagram to answer the following questions. (a) Which is the least reactive element? …………………………………………………………………………………………… [1] (b) Write the chemical formula of the compound formed when W and Z react. ……………………… [1] (c) Q, R and Z belong to Group VII. They are also known as halogens and exist as diatomic molecules. (i) The arrangement of electrons in Q is 2,8,18,7. Explain why Q