2022 Sec 4 NA Science Chemistry

2022 SECONDARY 4 Normal Academic Exam Paper NA Science Chemistry 1 Admiralty Sec SA2 2 Assumption English SA2 3 Bedok South Sec SA2 4 Chua Chu Kang Sec SA2 5 Fuchun Sec SA2 6 Pasir Ris Sec SA2 7 Peirce Sec SA2 8 Woodgrove Sec SA2 www.KiasuExamPaper.com 1

www.KiasuExamPaper.com 2

This question paper consists of 8 printed pages including this cover page. ADMIRALTY SECONDARY SCHOOL SUBJECT : Science (Chemistry) CODE/PAPER : 5105/3, 5107/3 LEVEL/STREAM : Secondary 4 Normal (Academic) DATE : 2 August 2022 TIME : 0800h – 0915h DURATION : 1 hour 15 minutes READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name, class and register number on the Optical Answer Sheet provided unless this has been done for you. 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 Optical Answer Sheet. Fill in the Optical 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 question paper. A copy of the Periodic Table is printed on page 8. The use of an approved scientific calculator is expected, where appropriate. DO NOT TURN OVER THIS PAPER UNTIL YOU ARE TOLD TO DO SO. PRELIMINARY EXAMINATION 2022 NAME: NO: CLASS: 20 www.KiasuExamPaper.com 3

2 1 Which of the following pieces of apparatus is most suitable for accurately measuring out 16.80 cm3 of water? 2 The graph below shows the heating curve of solid N. What does the graph suggest about solid N? A It is not pure. B It is a liquid at 0 qC. C It is an ionic compound. D It has a high melting point. A B C D temperature / qC time / min 0 www.KiasuExamPaper.com 4

3 3 The diagram below shows a common experimental set-up used to se parate mixtures in the laboratories. Which of the following mixtures can be separated into its compo nents using the set-up above? A argon and carbon dioxide B carbon and iron C petrol and kerosene D sand and water 4 The diagram below shows an experiment to obtain water from aqueous copper sulfate. Aqueous copper sulfate is a blue solution. After 1 0 minutes of heating, what are the colours of the liquids in the flask and the beaker? flask beaker A blue blue B blue colourless C colourless blue D colourless colourless water out water in beaker heat flask aqueous copper sulfate www.KiasuExamPaper.com 5

4 5 The table below shows information about four different compounds. Which of the following correctly shows the elements present in each compound? compounds elements A CO2 copper and oxygen B HCl carbon, hydrogen and lead C N2H4 hydrogen and nitrogen D PbO phosphorus and oxygen 6 The diagram below shows the electronic structure of an atom of element Q. In which group and period does element Q belong to? group period A II 2 B II 3 C III 2 D III 3 7 Calcium fluoride has the formula CaF2. Which statement best describes the bond formed between the two elements? A Each fluorine atom transfers one electron to a calcium atom. B Each fluorine atom shares one electron with a calcium atom. C Each calcium atom transfers two electrons, one to each of the fluorine atoms. D Each calcium atom shares two electrons, one with each of the fluorine atoms. 8 What is the relative formula mass, Mr, of ammonium nitrate, NH4NO3? A 23 B 42 C 45 D 80 www.KiasuExamPaper.com 6

5 9 The equation below shows the reaction that occurs when ethanol (C2H5OH) is burnt in air. C2H5OH (l) + xO2 (g) Æ yCO2 (g) + zH2O (l) What are the values of x, y and z needed to balance this equation? x y z A 3 2 1 B 3 2 3 C 7 4 2 D 7 4 6 10 In agricultural activities, farmers need to control the acidity of the soil. Which substance is used to neutralise the soil acidity? A calcium chloride B calcium hydroxide C calcium nitrate D calcium sulfate 11 Salt P reacts with aqueous sodium hydroxide to produce ammonia gas. Which of the following is a possible identity of salt P? A ammonium sulfate B calcium sulfate C potassium sulfate D sodium sulfate 12 Which method can be used to prepare the insoluble salt, lead sulfate? A By reacting excess lead metal with dilute sulfuric acid. B By reacting excess solid lead oxide with dilute sulfuric acid. C By reacting excess solid lead hydroxide with dilute sulfuric acid. D By reacting excess aqueous lead nitrate with aqueous sodium sulfate. 13 Which two chemicals will react to make the salt, copper(II) chloride? A copper metal and hydrochloric acid B copper(II) carbonate and hydrochloric acid C copper metal and sulfuric acid D copper(II) carbonate and sulfuric acid www.KiasuExamPaper.com 7

6 14 Statement 1: Zinc can react with nitric acid. Statement 2: Nitric acid is made up of three elements – hydrogen, nitrogen and oxygen. Which of the following is true? A Both statements are correct, and statement 2 explains statement 1. B Both statements are correct, but statement 2 does not explain statement 1. C Statement 1 is correct but statement 2 is incorrect. D Statement 2 is correct but statement 1 is incorrect. 15 Which of the following diagrams best represents the structure of an alloy? A B C D 16 Which of the following is found on the leftmost side of the Periodic Table? A halogens B non-metals C metals D noble gases 17 Six different elements T, U, W, X, Y and Z are indicated in the Periodic Table shown below. The letters T, U, W, X, Y and Z do not represent the chemical symbols of the elements. Which of the following statements is true? A W is less reactive than X. B U and Z are diatomic molecules. C W and X are elements in the same period. D Y and T are elements with six electrons in the outermost shell. www.KiasuExamPaper.com 8

7 18 Which of the following explains why the components of air can b e separated by fractional distillation? A The components have different boiling points. B The components have different colours. C The components have different densities. D The components have different relative molecular mass. 19 Which air pollutant is not correctly matched to its source? air pollutant source A carbon monoxide incomplete combustion of petrol B nitrogen oxides lightning activity C sulfur dioxide volcanoes D unburnt hydrocarbons complete combustion of fossil fuels 20 The diagram below shows the separation of crude oil into fractions. What are the possible uses of X and Y? X Y A making road surfaces fuel for diesel engines B fuel for diesel engines feedstock for petrochemicals C fuel for cooking and heating making road surfaces D lubricating machines making road surfaces END OF PAPER crude oil X Y www.KiasuExamPaper.com 9

8 www.KiasuExamPaper.com 10