Jurongville 2024 Prelim 4E Chemistry Paper 1

JVSS Prelim 2024 4E Chemistry 6092/01 [Turn over JURONGVILLE SECONDARY SCHOOL PRELIMINARY EXAMINATION 2024 Secondary 4 Express STUDENT NAME CLASS INDEX NUMBER CHEMISTRY 6092/01 Paper 1 Multiple Choice 07 August 2024 1 hour Additional Materials: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, class and index number in the spaces at the top of this page. There are forty 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 Multiple Choice Answer Sheet. 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 15. The use of an approved scientific calculator is expected, where appropriate. DO NOT OPEN THE BOOKLET UNTIL YOU ARE TOLD TO DO SO This document consists of 15 printed pages. Setter: Ms Ethel Chng For Examiner’s Use 40

2 JVSS Prelim 2024 4E Chemistry 6092/01 1 The setup used to dry gas Q is shown. What can be deduced about gas Q? A Gas Q is denser than air. B Gas Q is either acidic or neutral. C Gas Q is insoluble in water. D Gas Q is soluble in concentrated sulfuric acid. 2 The diagram shows a method of measuring the rate of reaction. Which reaction is not suitable for using this method to measure its rate? A C6H12O6 → 2C2H5OH + 2CO2 B CaCO3 + 2HCl → CaCl2 + H2O + CO2 C Mg + 2HCl → MgCl2 + H2 D NaOH + NH4Cl → NaCl + NH3 + H2O 3 A food colouring is analysed by paper chromatography. From its chromatogram, what is the Rf value of the least soluble dye? A 0.25 B 0.30 C 0.35 D 0.40 moist gas Q in concentrated sulfuric acid dry gas Q out solvent front start 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 ● ●

3 JVSS Prelim 2024 4E Chemistry 6092/01 [Turn over 4 From which mixture can the first substance be obtained by adding water, stirring and filtering? A copper and copper(II) chloride B iodine and magnesium carbonate C silicon dioxide and zinc oxide D sodium chloride and sodium sulfate 5 A chemist is given an unknown white powder. What should the chemist do to determine the purity of the unknown substance? A burn it in excess oxygen B conduct a solubility test in water C measure its melting point D pass electricity through it 6 An aqueous solution contains a mixture of Cl−, CO32− and SO42− ions. Which aqueous reagent can be added to remove only CO32− ions from the mixture? A AgNO3 B Ba(NO3)2 C HNO3 D NaOH 7 The diagrams represent the arrangement of particles in substance T at two different temperatures. −110 °C 30 °C What are the melting and boiling points of substance T? melting point / °C boiling point / °C A −157 −152 B −112 −108 C −101 −35 D −7 59

4 JVSS Prelim 2024 4E Chemistry 6092/01 8 A beaker containing gas 1 is inverted over a porous pot containing gas 2 as shown. Which two gases will cause no change in the water level? A carbon monoxide and nitrogen B carbon dioxide and nitrogen dioxide C ethane and ethene D ethane and propane 9 A particle, with a +4 charge, contains 48 particles in its nucleus and 18 electrons. What are the numbers of neutrons and protons found in its nucleus? number of neutrons number of protons A 26 22 B 28 20 C 30 18 D 34 14 10 Which substance contains both covalent and ionic bonds? A hydrogen chloride B iron(II) sulfide C manganese dioxide D potassium nitrate water beaker gas 1 gas 2 porous pot

5 JVSS Prelim 2024 4E Chemistry 6092/01 [Turn over 11 Phosphorus exists in several allotropes. White phosphorus is a soft solid with a melting point of 44 °C, while red phosphorus is a hard solid with a melting point of 590 °C. White phosphorus consists of discrete P 4 molecules, while red phosphorus consists of a network of P4 units that have been linked. Which statement is true of these two forms of phosphorus? A Both forms are soluble in organic solvents and water. B Both forms can conduct electricity. C Both forms have a simple molecular structure. D Both forms have strong covalent bonds between phosphorus atoms. 12 Metals have positive ions in a ‘sea’ of electrons. Which statement(s) is/are correct? 1 Aluminium provides more electrons for the ‘sea’ than magnesium. 2 The ‘sea’ of electrons allows metals to conduct electricity only in solid state. 3 The ‘sea’ of electrons cannot be found in alloys. A 1, 2 and 3 B 1 and 3 only C 1 only D 2 and 3 only 13 A molecule of maleic acid has its structure shown. C C How many valence electrons are not shared in this molecule? A 8 B 14 C 16 D 28 14 How many hydrogen atoms are there in 17 g of phosphine, PH3? A 3.01 × 1023 B 6.02 × 1023 C 9.03 × 1023 D 1.20 × 1024 C O O H H H C O O H

6 JVSS Prelim 2024 4E Chemistry 6092/01 15 On heating with carbon, the oxide of metal X is reduced. 2XO + C → 2X + CO2 When 120 g of XO is heated, 18 dm3 of CO2 is produced. What is the relative atomic mass of X? A 56 B 59 C 64 D 65 16 The industrial production of ammonia is carried out via the Haber process. Suppose unreacted gases are not recycled, w hat volumes of nitrogen and hydrogen are required to produce 600 dm3 of ammonia in a process that is only 15% efficient? volume of N2 / dm3 volume of H2 / dm3 A 45 135 B 255 765 C 300 900 D 2000 6000 17 On heating, sodium hydrogen carbonate decomposes. 2NaHCO3(s) → Na2CO3(s) + H2O(l) + CO2(g) When all 105 g of sodium hydrogen carbonate undergoes thermal decomposition, what is the volume of 0.50 mol/dm3 of hydrochloric acid required to exactly react with the residue formed? A 0.40 dm3 B 0.80 dm3 C 1.25 dm3 D 2.50 dm3 18 The table shows the results for the electrolytic purification of copper, using aqueous copper(II) sulfate as the electrolyte. initial mass / g final mass / g impure copper anode 110 10 pure copper cathode 10 90 What was the percentage impurity of the impure copper anode? A 9.1% B 27.3% C 72.7% D 90.9%

7 JVSS Prelim 2024 4E Chemistry 6092/01 [Turn over 19 The diagram shows the electrolytic production of aluminium. Which equations represent the reactions taking place at the inert electrodes? negative electrode positive electrode A Al3+ + 3e− → Al 2O2− → O2 + 4e− B Al3+ → Al + 3e− 2O2− + 4e− → O2 C 2O2− → O2 + 4e− Al3+ + 3e− → Al D 2O2− + 4e− → O2 Al3+ → Al + 3e− 20 Two cells undergoing electrolysis are connected in series. What are the substances formed at the platinum electrodes? cell 1 cell 2 anode cathode anode cathode A nitrogen hydrogen chlorine hydrogen B oxygen hydrogen oxygen copper C oxygen silver chlorine copper D oxygen silver oxygen hydrogen negative electrode positive electrode Pt dilute AgNO3(aq) concentrated CuCl2(aq) Pt Pt Pt cell 1 cell 2 molten aluminium oxide

8 JVSS Prelim 2024 4E Chemistry 6092/01 21 In combustion reactions, some substances release more energy than others. The enthalpy change of combustion, ΔH c, indicates the amount of energy released when one mole of a substance burns completely in oxygen. The table shows the ΔHc of four substances. substance formula state ΔHc in kJ/mol ethanol C2H5OH liquid −1367 hydrogen H2 gas −286 octane C8H18 liquid −5470 propane C3H8 gas −2220 Which substance will release the most energy when 1 g of it is completely combusted? A eth