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 informa