2023 NYGH Chem Prelims P1

Class Centre/Index Number Name Preliminary Examination 2023 Secondary 4 CHEMISTRY Paper 1 Multiple Choice 6092/01 1 hour Friday 25 August 1200 – 1300 Additional materials: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue, correction fluid or tape. Write your name, register number and class in the spaces at the top of this page and on the Answer Sheet in the spaces provided. 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 Answer Sheet. Read the instructions on the Answer Sheet very carefully. 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. This document consists of 14 printed pages and 2 blank page. Setter(s): KO NANYANG GIRLS' HIGH SCHOOL [Turn over

2 1 Which of the following shows the states of matter before and after the sublimation of iodine? before after A B C D 2 The diagram below shows a descending chromatogram of a sample containing substance S. The solvent tank is at the top of the set up. Which measurements are used to find the Rf value of S? A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4 S sample solvent tank 1 2 3 4

3 [Turn over 3 A student wants to measure the time taken for 1.5 g of zinc powder to dissolve in 50 cm3 of dilute sulfuric acid. Which apparatus is essential to complete the experiment? 1 stopwatch 2 measuring cylinder 3 gas syringe 4 balance A 1, 2 and 4 B 1 and 2 only C 1 and 4 only D 2, 3 and 4 4 Which row identifies a chemical change and a physical change? chemical change physical change A boiling ethanol burning ethanol B burning ethanol evaporating ethanol C dissolving ethanol in water burning ethanol D evaporating ethanol dissolving ethanol in water 5 X3- contains 24 particles. 17 of them are charged particles. Which statement about the ion is correct? A It contains 7 neutrons and 7 electrons. B It contains 7 nucleons and 10 electrons. C It contains 7 protons and 10 electrons. D It contains 10 protons and 7 electrons. 6 Which of the following contains both covalent and ionic bonds? A sodium methanoate B methyl ethanoate C lithium chloride D calcium nitride

4 7 The following shows structures of three macromolecules T, U and V. Identify T, U and V. T U V A diamond, C silicon carbide, SiC graphite, C B graphite, C diamond, C silicon carbide, SiC C silicon carbide, SiC silicon dioxide, SiO2 graphite, C D silicon dioxide, SiO2 silicon carbide, SiC graphite, C 8 Which compound contains the highest percentage of nitrogen by mass? A N2H4 B NH4Cl C KNO3 D Mg(NO3)2 9 The carbonate of element Y undergoes thermal decomposition. YCO3(s) → YO(s) + CO2(g) 14.8 g of YCO3 is heated and 1.8 dm3 of carbon dioxide, measured at room temperature and pressure, is produced. What is the relative atomic mass of Y? A 40 B 88 C 137 D 197 T U V

5 [Turn over 10 4.38 g of a metal oxide, ZO2 contains 2.63 g of metal Z. What is the identity of Z? A Ti22 48 B Mn25 55 C Sn50 119 D Pb82 207 11 The equations show the reactions involved in the formation of sulfuric acid from sulfur. S + O2 → SO2 2SO2 + O2 → 2SO3 SO3 + H2O → H2SO4 How many moles of sulfuric acid are formed from 1.00 mole of sulfur? A 0.50 B 1.00 C 2.00 D 4.00 12 Calcium reacts with dilute nitric acid to form calcium nitrate and hydrogen. Ca + 2HNO3 → Ca(NO3)2 + H2 4.0 g of calcium react with exactly 100 cm3 of 2 mol/dm3 nitric acid to give 2.4 dm3 of hydrogen, at room temperature and pressure. Which row would give 4.8 dm3 of hydrogen at room temperature and pressure? mass of calcium/ g nitric acid volume/ cm3 concentration/ mol/dm3 A 4.0 100 2 B 4.0 200 1 C 8.0 100 1 D 8.0 200 2

6 13 Four different conditions under which lithium bromide is electrolysed using inert electrodes are listed. 1 concentrated aqueous lithium bromide 2 dilute aqueous lithium bromide 3 molten lithium bromide 4 solid lithium bromide Under which conditions is a brown vapour formed? A 1 and 2 B 1 and 3 C 3 and 4 D 3 only 14 What would be observed when aqueous copper(II) sulfate is electrolysed using a positive carbon electrode and a negative copper electrode? at the positive carbon electrode at the negative copper electrode A electrode dissolves brown solid deposit B electrode dissolves effervescence C effervescence brown solid deposit D effervescence electrode dissolves 15 In an electrolysis experiment, the same amount of charge deposited 6.5 g of chromium and 4 g of copper. The charge on the copper ion was 2+. What was the charge on the chromium ion? [Ar: Cr, 52; Cu, 64] A +1 B +2 C +3 D +4 16 The hydrogen fuel cell is an alternative source of fuel to petrol. What is incorrect about the hydrogen fuel cell? A Chemical energy is converted to electrical energy. B Hydrogen gas is oxidised in the process. C The reaction that takes place is endothermic. D Water is the only product.

7 [Turn over 17 The energy profile diagram shows the energy changes that occur as a reaction takes place. From the diagram, which statement about this reaction is correct? A Less energy were needed during bond breaking than released during bond forming. B In the reaction, there was an increase in temperature of the surrounding. C This reaction could be 6CO2 + 6H2O → C6H12O6 + 6O2. D The reaction has a negative ΔH value. 18 A reversible reaction is exothermic in the forward reaction and the heat produced is 273 kJ/ mol. The activation energy for the forward reaction is 80 kJ/ mol. What is the activation energy of the reverse reaction? A 80 kJ/ mol B 193 kJ/ mol C 273 kJ/ mol D 353 kJ/ mol 19 An equation for respiration is as shown: C6H12O6 + 6O2 → 6H2O + 6CO2 When 32.0 g of O2 is reacted, 472 kJ of energy is released. What is the enthalpy change of this reaction? A – 2832 kJ/ mol B – 472 kJ/ mol C + 2832 kJ/ mol D + 472 kJ/ mol energy progress of reaction reactants products

8 20 Decomposition of hydrogen peroxide produces oxygen gas as shown in the equation. 2H2O2 → 2H2O + O2 Experiment 1 was carried out with 50 cm3 of 0.1 mol/dm3 hydrogen peroxide and the results are shown in curve 1. What change was made to the experiment to produce curve 2? A Using 50 cm3 of 0.05 mol/dm3 of hydrogen peroxide B Using 125 cm3 of 0.05 mol/dm3 of hydrogen peroxide C Using 50 cm3 of 0.15 mol/dm3 of hydrogen peroxide D Using 125 cm3 of 0.15 mol/dm3 of hydrogen peroxide 21 Iron reacts with dilute hydrochloric acid at a constant temperature of 25oC. Which statement about the rate of this reaction is correct? A It decreases as the reaction proceeds. B It decreases then increases as the reaction proceeds. C It increases as the reaction proceeds. D It remains the same as the reaction proceeds. 22 Aqueous iron(III) chloride, FeCl3, reacts with aqueous potassium iodide, KI. aFeCl3 + bKI → cFeCl2 + dKCl + I2 Which statements are correct? 1 In the balanced equation, a, b, c and d have the same value. 2 Potassium iodide is an oxidising agent. 3 A dark brown solution is produced in the reaction. A 1 and 2 B 1 and 3 C 2 and 3 D 1,2 and 3 volume of oxygen gas / cm3 t