Pasir Ris 2024 4E Chem Prelim P1

Name Class Register Number SECONDARY 4 EXPRESS PRELIMINARY EXAMINATION 2024 CHEMISTRY Paper 1 Multiple Choice Monday 0920 – 1020 6092/01 26 Aug 2024 1 hour Additional Material: Multiple Choice Answer Sheet 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 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 14. The use of an approved scientific calculator is expected, where appropriate. This document consists of 14 printed pages, including the cover page. Setter: Mr Chua Khoon Wee [Turn over Pasir Ris Secondary School

PRSS_2024_S4E_PRELIM_CHEM_ 6092_P1 2 1 Which apparatus can be used to determine the end-point of the neutralisation reaction between hydrochloric acid and potassium hydroxide? A electronic balance B gas syringe C stopwatch D thermometer 2 Which property of a liquid ester can be used to check its purity before use as a food flavouring? A boiling point B colour C smell D solubility in water 3 Which sequence of procedures is used to separate a pure, dry sample of hydrated copper( II) sulfate, CuSO 4•5H2O, from a mixture containing hydrated copper( II) sulfate and calcium carbonate, CaCO3? A dissolve in water → distillation → crystallisation B dissolve in water → filtration → crystallisation C distillation → crystallisation → heating to remove all water D fractional distillation → filtration → heating to remove all water 4 The melting and boiling points of four substances are given. substance melting point / oC boiling point / oC W 50 90 X 70 600 Y –30 –12 Z –15 101 At what temperature would there be exactly two substances in liquid state? A –20 oC B 0 oC C 16 oC D 60 oC 5 The rate of diffusion of two gases is measured at constant pressure. Which gas would diffuse the fastest? A carbon monoxide at 25 oC B carbon monoxide at 50 oC C oxygen at 25 oC D oxygen at 50 oC

PRSS_2024_S4E_PRELIM_CHEM_ 6092_P1 3 6 Which ion contains the smallest number of electrons? A B3+ B Be2+ C H– D He+ 7 An element J forms an ion J2–. The electronic configuration of this ion is 2.8. Which statement is true? A J is in Group 2 and Period 2. B J is in Group 2 and Period 3. C J is in Group 16 and Period 2. D J is in Group 16 and Period 3. 8 A new substance was discovered and a series of experiments was conducted on it. Which observation suggests that the substance cannot be an element? A It has a fixed boiling point. B It dissolves in water to form a yellowish-green solution. C When heated in air, it can form oxides with two different chemical formulae. D When heated strongly, a brown solid and a yellow gas are produced. 9 The electrical conductivities of two compounds, M and N, are shown in the table. M N conductivity of the compound in liquid state good good conductivity of the mixture obtained by adding the compound to water good does not conduct M N A Al2O3 SiO2 B Na2O Al2O3 C Na2O SiO2 D SiO2 Al2O3 10 Which substance contains both ionic and covalent bonds? A ammonium chloride B hydrogen chloride C lithium oxide D silicon dioxide

PRSS_2024_S4E_PRELIM_CHEM_ 6092_P1 4 11 The magnitude of property X of the first five elements from the third period of the Periodic Table, P, Q, R, S and T is shown. P, Q, R, S and T have consecutive atomic numbers. The letters do not represent the symbols of the elements. Which row correctly identifies property X and element R? property X element R A electrical conductivity Al B electrical conductivity Si C melting point Al D melting point Si 12 The labels of two bottles of colourless solutions fell off in the Chemistry laboratory. One is known to be sodium sulfate solution while the other is potassium carbonate solution. Which chemical can be added to identify the solutions? A aqueous ammonia B aqueous barium nitrate C blue litmus solution D dilute nitric acid 13 The table shows the results of tests carried out to examine the air in an industrial area. tests observations add aqueous calcium hydroxide white precipitate formed add anhydrous copper(II) sulfate white solid turned blue add acidified potassium manganate(VII) purple solution decolourised Which of the following sets of gases was present in the sample of air? A CO, H2, SO2 B CO2, H2, O2 C CO2, H2O, SO2 D H2O, O2, SO2 X P Q R S T

PRSS_2024_S4E_PRELIM_CHEM_ 6092_P1 5 14 The table shows how different indicators change colour over different pH ranges. When a weak alkali is added to a strong acid, the following titration curve is obtained. Which indicator is the most suitable for the above titration? A indigo carmine B methyl red C methyl violet D phenolphthalein 15 Which method can be used to distinguish 1.00 mol/dm 3 of dilute hydrochloric acid from 1.00 mol/dm3 of dilute ethanoic acid? 1 Using a pH meter. 2 Determining the volume of 1.00 mol/dm3 sodium hydroxide solution needed to completely neutralise 25.0 cm3 of the acids separately. 3 Measuring the total volume of hydrogen gas formed when excess magnesium is added to 25.0 cm3 of the acids separately. A 1, 2 and 3 B 1 and 2 only C 2 and 3 only D 1 only

PRSS_2024_S4E_PRELIM_CHEM_ 6092_P1 6 16 Ammonium nitrate, NH4NO3, and ammonium sulfate, (NH4)2SO4, are used as fertilisers. Which ammonium salt has a greater percentage b y mass of nitrogen and shows the correct effect on pH of soil that contains both H+ and OH– ions? greater percentage of nitrogen by mass effect on pH of soil A ammonium nitrate decrease B ammonium nitrate increase C ammonium sulfate decrease D ammonium sulfate increase 17 Element K has three naturally occurring isotopes, K–24, K–25 and K–26. What is the relative atomic mass of element K given that K–24 has an abundance of 79% and K–26 has an abundance of 10%? A 21.6 B 24.3 C 25.0 D 25.3 18 The chemical equation for the thermal decomposition of calcium nitrate is shown. 2Ca(NO3)2 (s) → 2CaO (s) + 4NO2 (g) + O2 (g) What is the volume of gas produced at room temperature and pressure when 0.40 mol of calcium nitrate was heated until no further decomposition? A 4.8 dm3 B 9.6 dm3 C 19.2 dm3 D 24.0 dm3 19 Ammonium salts produce ammonia gas when heated with aqueous sodium hydroxide. Which ammonium salt will produce the largest volume of ammonia gas when heated with excess aqueous sodium hydroxide? A 1.00 mol (NH4)2CO3 B 1.00 mol (NH4)3PO4 C 2.00 mol NH4Cl D 2.50 mol NH4NO3

PRSS_2024_S4E_PRELIM_CHEM_ 6092_P1 7 20 ZnO and CO2 are produced when ZnCO3 is heated strongly. What is the percentage yield of ZnO if 125 g of ZnCO3 produces 75 g of ZnO on heating? A 60.0% B 64.8% C 92.6% D 100% 21 Methylamine, CH3NH2, has very similar chemical properties to ammonia. Methylamine reacts with hydrogen chloride to form a white crystalline salt, methylammonium chloride. CH3NH2 + HCl → CH3NH3Cl A sample of methylammonium chloride is heated with aqueous sodium hydroxide. What are the products formed? A ammonia, sodium chloride and water B ammonia, sodium hydrogencarbonate and sodium chloride C methy