ACSBR 4NA 5105 2024 prelim Paper 3 EDITED

Anglo-Chinese School (Barker Road) PRELIMINARY EXAMINATION 2024 SECONDARY FOUR NORMAL (ACADEMIC) SCIENCE (CHEMISTRY) PAPER 3 5105/3 1 HOUR 15 MINUTES (FOR BOTH PAPERS) 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 the last page. The use of an approved scientific calculator is expected, where appropriate. This document consists of 8 printed pages.

Anglo-Chinese School (Barker Road) Preliminary Examination 2024 Secondary Four Normal (Academic) Science (Chemistry) 5105 Paper 3 Page 2 1 Which substance is a liquid at 50 oC? melting point/ oC boiling point/ oC A –117 43 B –93 69 C 36 49 D 55 103 2 A salt is made by adding an excess of an insoluble metal oxide to an acid. Which method is used to remove excess metal oxide from the mixture? A chromatography C distillation B crystallisation D filtration 3 Dye X is compared with four other dyes, P, Q, R and S using chromatography. The chromatogram is shown below. What can be deduced from the results of chromatography? A Dyes P and S are insoluble in the solvent. B Dyes P and S are pure. C X consists of dyes Q, R and S. D X contains two different components. solvent front start line X P Q R S

Anglo-Chinese School (Barker Road) Preliminary Examination 2024 Secondary Four Normal (Academic) Science (Chemistry) 5105 Paper 3 Page 3 4 Which diagram shows a representation of a mixture of compounds? 5 The number of atoms can be derived from the chemical formula of the compound. Which row is not correct? formula number of atoms A CaCO3 1 calcium, 1 carbon, 3 oxygen B C2H5OH 1 carbon, 5 hydrogen, 1 oxygen C KOH 1 hydrogen, 1 oxygen, 1 potassium D H2SO4 2 hydrogen, 4 oxygen, 1 sulfur 6 In the Periodic Table, how does the metallic character of the elements vary from left to right across a period? A It decreases. B It increases. C It increases then decreases. D It stays the same. 7 X and Y exist as diatomic molecules. X is less reactive than Y. What are elements X and Y? X Y A bromine iodine B iodine bromine C potassium sodium D sodium potassium A B C D

Anglo-Chinese School (Barker Road) Preliminary Examination 2024 Secondary Four Normal (Academic) Science (Chemistry) 5105 Paper 3 Page 4 8 The graph shows how the pH of soil in a field changes over time. At which point was the soil neutral? 9 Which of the following oxides is amphoteric? A aluminium oxide C copper(II) oxide B calcium oxide D iron(III) oxide 10 Which statement about acids and bases is correct? A Acids react with metal oxides to form salts and hydrogen. B Alkalis are bases which are insoluble in water. C Neutralisation is the reaction between acids and bases. D Potassium hydroxide dissolves in water and turns blue litmus red. 11 Aqueous solution X is added to aqueous ammonium chloride. The mixture is heated and ammonia gas is given off. Which is X? A ammonium sulfate C sodium chloride B hydrochloric acid D sodium hydroxide time A B C D pH of soil 11 9 7 5 3

Anglo-Chinese School (Barker Road) Preliminary Examination 2024 Secondary Four Normal (Academic) Science (Chemistry) 5105 Paper 3 Page 5 12 The electronic structures of atoms P and Q are shown. P and Q react to form an ionic compound. What is the formula of this compound? A PQ2 C Q2P B P2Q D QP2 13 Which is the most abundant noble gas in clean air? A argon C krypton B helium D xenon 14 Some processes that produce pollutants are listed below. 1 combustion of fossil fuels 2 lightning activity 3 volcanic eruptions Which process may produce sulfur dioxide? A 1 and 3 only C 1, 2 and 3 B 2 and 3 only D 3 only 15 Four shiny steel paper clips are placed in test-tubes and left for some days. In which test-tube does the paper clip rust? A B C D key = electrons P Q drying agent cotton wool air paper clip paper clip tap water paper clip greased paper clip air oil boiled tap water

Anglo-Chinese School (Barker Road) Preliminary Examination 2024 Secondary Four Normal (Academic) Science (Chemistry) 5105 Paper 3 Page 6 16 The reactions of four metals, W, X, Y and Z, with water, steam or dilute hydrochloric acid are described. W reacts violently with cold water. X does not react with cold water but reacts with steam. Y reacts slowly with cold water. Z does not react with hydrochloric acid. What is the order of reactivity of W, X, Y and Z? most reactive least reactive A W Y X Z B W X Y Z C Z X Y W D Z Y X W 17 What is the main source of energy in natural gas? A carbon monoxide C methane B hydrogen D nitrogen 18 Which substance is an alkane? A C4H8 C C6H14 B C5H10 D C7H14 19 The structure of a compound is shown. Which row correctly describes the properties of the compound? decolourises aqueous bromine hydrocarbon A no no B no yes C yes no D yes yes

Anglo-Chinese School (Barker Road) Preliminary Examination 2024 Secondary Four Normal (Academic) Science (Chemistry) 5105 Paper 3 Page 7 20 Which statement about recycling of plastics is correct? A During the chemical method of recycling, plastic waste is converted into long-chain alkanes and alkenes. B Plastics can be recycled by melting and cooling small pieces of polyethene waste before being pulled and cut into pellets. C Plastic waste is converted into different raw materials like short-chain alkanes and alkenes through chemical reactions such as combustion. D Recycling of plastic waste is important because plastics are biodegradable.

Anglo-Chinese School (Barker Road) Preliminary Examination 2024 Secondary Four Normal (Academic) Science (Chemistry) 5105 Paper 3 Page 8 1 OFFICIAL (CLOSED)