qtss comb chem prelim 2024 p4 answer

This document consists of 11 printed pages. Name: ………………………………………………….. ( ) Class: Sec 4 SG 5 / 6 Queenstown Secondary School Preliminary Examination 2024 Secondary Four Normal (Academic) Science (Chemistry) 5105/03 30 July 2024 Time: 1015 – 1130h Tuesday Papers 3 and 4: 1 hour 15 minutes Setter: Additional Materials: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name, class and index number on the Answer Sheet in the spaces provided. There are twenty questions on this paper. Answer all questions. For each question there are four possible answers A, B, C and D. Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet. Read the instructions on the Answer Sheet very carefully. Answers to Paper 3 and Paper 4 must be handed in separately. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. 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. Any rough working should be done in this booklet. A copy of the Periodic Table is printed on page 11. The use of an approved scientific calculator is expected, where appropriate.

2 Queenstown Secondary School [Turn over 1 The diagrams show two methods of collecting gases. Which row gives the properties of a gas that can be collected by both methods? property 1 property 2 A insoluble in water denser than air B insoluble in water less dense than air C soluble in water denser than air D soluble in water less dense than air 2 Three separations are listed. 1 obtaining water from sodium chloride solution 2 obtaining solid copper(II) sulfate from copper(II) sulfate solution 3 obtaining sand from a mixture of sand and sodium chloride solution 1 2 3 A distillation crystallisation filtration B distillation evaporation sublimation C filtration crystallisation sublimation D filtration evaporation filtration

3 Queenstown Secondary School [Turn over 3 Samples of tinned apricots, beans, corn and tomatoes are tested for additives by using chromatography. The chromatograms are compared with those of three artificial additives, P, Q and R. The results are as follows. Which tinned food does not contain any artificial additives? A apricots B beans C corn D tomatoes 4 Substance X has a melting point of –7°C and a boiling point of 79°C. Which diagram shows the correct arrangement of particles of substance X under room conditions? [liquid at room conditions] A C B