SNGS 2024 S4 Prelim Paper 1 QP

This document consists of 22 printed pages. [Turn over Name: _______________________________ ( ) Class:___________ PRELIMINARY EXAMINATION GENERAL CERTIFICATION OF EDUCATION ORDINARY LEVEL _____________________________________________________________________ CHEMISTRY 6092/01 Paper 1 Multiple Choice 28 August 2024 1 hour Additional materials: Multiple Choice Answer Sheet _____________________________________________________________________ READ THESE INSTRUCTIONS FIRST Write your name, register number and class on the Answer Sheet using a soft pencil. There are 40 questions in 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. Amendments may be done using a soft eraser. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet. A copy of the Periodic Table is printed on page 22. The use of an approved scientific calculator is expected, where appropriate. For Examiner’s Use Total (40)

2 T 1 An ion X2– has m nucleons and n electrons. What does the nucleus of an atom of X contain? number of protons number of neutrons A n – 2 m – n B n – 2 m – (n – 2) C n + 2 m – (n – 2) D n + 2 m – (n + 2) 2 Which of the following substances could be hydrogen chloride? melting point /°C boiling point /°C electrical conductivity in molten state in aqueous state A –100 –85 none good B –114 78 none none C 190 290 none insoluble D 1081 1565 good good 3 The table below shows some information about four substances labelled P to S. substance appearance observations P colourless liquid boils away, leaving a white residue Q colourless gas burns in oxygen to form water and carbon dioxide only R yellow solid splits up by electricity in molten state to form a metal and a gas S white solid burns in air to form an oxide as the only product Based on the observations, which of these substances P, Q, R and S are compounds? A P and Q only B Q and R only C R and S only D Q, R and S only

3 4 The graph below shows the cooling curve of carbon disulfide. Which one of the following statements is true? A The boiling point of carbon disulfide is -112 °C. B From t1 to t2, the spaces between particles are increasing. C From t2 to t3, there is no solid present. D From t3 to t4, all the particles of carbon disulfide are vibrating in fixed positions.

4 5 The diagram below shows an apparatus for measuring the rates of diffusion of gases. The time taken for 100 cm 3 of some gases at room temperature and pressure to diffuse from this apparatus is shown in the table. gas time /s CO 132 Cl2 211 CH4 100 O2 141 What will be the time taken for nitrogen gas to diffuse from this apparatus? A 66 s B 72 s C 100 s D 132 s 6 Which of the following is an example of oxidation? A Bromine becomes colourless when added to aqueous sodium iodide. B Nitrogen dioxide is removed during the reaction occurring in a motor car’s catalytic convertor. C Iron(II) hydroxide is precipitated from a solution of iron(II) ions. D Silver anode becomes smaller during electrolysis. 7 A textbook writes ‘Nitric acid, HNO3, is a strong oxidising agent’. Which of the following cannot be a product of nitric acid in its reaction with a reducing agent? A N2 B NO C NO2 D N2O5

5 8 The atomic radius of some Group 1 elements of the Periodic Table is given. element atomic radius /pm K 231 L 152 M 248 N 186 Which of the following shows the correct ascending order of melting point for the elements? lowest → highest A L K M N B L N K M C M K L N D M K N L 9 Which of the following statements correctly describes a trend in the properties of the elements, going from left to right of Period 2 of the Periodic Table? A The ability to form positive ions decreases. B The number of electron shells increases. C The ionic charge of the element increases. D The oxidizing ability of the element decreases.

6 10 Hydrated sodium carbonate has the formula Na 2CO3.nH2O. On strong heating, hydrated sodium carbonate decomposes completely into water and anhydrous sodium carbonate, Na2CO3. The formula of hydrated sodium carbonate was found by the following procedure. A mass of hydrated sodium carbonate was heated strongly in a crucible until decomposition was complete. The following results were obtained. Mass of empty crucible = 11.50 g Mass of crucible + hydrated sodium carbonate = 17.22 g Mass of crucible + anhydrous sodium carbonate = 13.62 g These data suggests that the formula for hydrated sodium carbonate is A Na2CO3.3H2O B Na2CO3.5H2O C Na2CO3.8H2O D Na2CO3.10H2O 11 The mineral dolomite is a double carbonate of magnesium and calcium, with the formula CaMg(CO3)2. When 2.00 g of an impure sample of dolomite was completely dissolved in excess hydrochloric acid, 0.45 g of carbon dioxide was given off. What is the percentage purity of the sample? CaMg(CO3)2 + 4HCl → MgCl2 + CaCl2 + 2CO2 + 2H2O A 22.5% B 47.0% C 77.5% D 94.1%

7 12 Dilute sulfuric acid, dilute nitric acid, and dilute e thanoic acid were separately titrated with 0.10 mol/dm3 aqueous sodium hydroxide . The same volume and concentration of each acid was used. In order to react completely, A all three acids would require the same volume of aqueous sodium hydroxide. B ethanoic acid and nitric acid would require the same volume of aqueous sodium hydroxide but sulfuric acid would require more. C nitric acid would require more aqueous sodium hydroxide than ethanoic acid but less than sulfuric acid. D sulfuric acid and nitric acid would require the same volume of aqueous sodium hydroxide but ethanoic acid would require less. 13 The graph shows the changes in pH when solid P was added to a beaker containing solution Q. What could P and Q be? P Q A aluminium oxide dilute hydrochloric acid B potassium oxide dilute hydrochloric acid C sodium oxide dilute ethanoic acid D zinc oxide dilute ethanoic acid mass of P added

8 14 A student mixed two aqueous solutions of ionic compounds at a time and made the following observations. solution A solution B observations Sr(ClO3)2 Mg(IO3)2 a precipitate formed Mg(IO3)2 Ni(ClO3)2 a precipitate formed MgCrO4 Pb(ClO3)2 a precipitate formed MgCrO4 Ca(ClO3)2 no visible change Which conclusion is correct based on these observations? A Only Ni(IO3)2 and Mg(ClO3)2 are insoluble. B Only Ni(IO3)2 and PbCrO4 are insoluble. C Sr(IO3)2, Ni(IO3)2 and PbCrO4 are insoluble. D Sr(IO3)2, Ni(IO3)2, PbCrO4 and CaCrO4 are insoluble. 15 Which is the best method to make lead (II) sulfate? A Adding lead (II) chloride to barium sulfate. B Adding lead (II) oxide to dilute sulfuric acid. C Adding lead (II) oxide to excess dilute nitric acid followed by dilute sulfuric acid. D Adding lead (II) oxide to dilute hydrochloric acid followed by ammonium sulfate. 16 A gaseous mixture of ammonia, hydrogen, sulfur dioxide and chlorine was passed through the apparatus shown below. Only one gas was collected in the gas jar. What is the property of the gas collected in the gas jar? A It bleaches moist red litmus paper. B It extinguishes a lighted splint with a pop sound. C It turns acidified potassium manga