AES Prelim P1

Name: ………………………………( ) This Question Paper consists of 19 printed pages including this page. [Turn over AASSUMPTION ENGLISH SCHOOL PRELIMINARY EXAMINATION 2024 CHEMISTRY 6092 / 01 ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL ASSUMPTION ENGLISH SCHOOL LEVEL: Sec 4 Express DATE: 28 August 2024 CLASS: Sec 4/1 DURATION: 1 hour Additional materials provided: 1 sheet of OAS paper INSTRUCTIONS TO CANDIDATES Do not open this booklet until you are told to do so. Write your NAME and INDEX NUMBER at the top of this page and on the OAS paper. Shade your index number on the OAS paper. MULTIPLE CHOICE QUESTIONS (40 marks) There are 40 questions in this section. Answer ALL questions. For each question, there are four possible answers A, B, C and D. Choose the correct answer and record your choice in soft or 2B pencil on the OAS paper provided. Do NOT fold or bend the OAS paper. For Examiner’s use: Paper 1 / 40 A copy of the Periodic Table is provided on Page 19. The use of an approved scientific calculator is expected where appropriate. At the end of the examination, hand in your OAS paper and question booklet separately.

2 6092/01/4E/PRELIM/2024 SECTION A: MULTIPLE CHOICE QUESTIONS [40 marks] There are forty questions in this section. 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 on the OAS in soft pencil. 1 An experiment was conducted to measure the temperature change caused by adding a known quantity of sodium carbonate to an excess of dilute acid. Besides a thermometer and styrofoam cup, these apparatus are available. 1 gas syringe 2 mass balance 3 measuring cylinder 4 stopwatch Which pieces of apparatus are needed for this experiment? A 1, 2, 3 and 4 B 2 and 3 only C 2 and 4 only D 4 only 2 An impure sample of compound X melted over a range of 162°C – 168°C. X was purified and its melting point was measured again. Which row correctly shows the method of purifying X and the melting point of pure X? method of purifying X melting point of pure X / °C A crystallisation 160 B distillation 160 C crystallisation 170 D distillation 170

3 6092/01/4E/PRELIM/2024 [Turn over 3 Chromatography was carried out to examine the dyes present in a sample of paint. The same sample of paint was used for the two chromatograms shown below. Which statement best explains the difference in the results observed? A A more concentrated sample of paint was used in chromatogram 1. B Chromatogram 1 proceeded for a longer time than chromatogram 2. C Different solvents were used in both chromatograms. D The solvents moved up the paper at different speeds. 4 A gas was released at point E in the set-up shown below. Which gas turns damp universal indicator paper red most quickly? A carbon monoxide B chlorine C hydrogen bromide D nitrogen dioxide solvent front start line chromatogram 1 chromatogram 2 E damp universal indicator paper

4 6092/01/4E/PRELIM/2024 5 Gas Y turns moist red litmus paper blue, is soluble in water and less dense than air. Which diagram shows the best method to collect a dry sample of gas Y? 6 Solid samples of ammonium chloride, silver chloride and sodium chloride were accidentally mixed together. Which sequence outlines the best method to obtain a pure and dry sample of each substance? A dissolving, filtration, sublimation, crystallisation B dissolving, fractional distillation, filtration, evaporation C sublimation, dissolving, filtration, evaporation D sublimation, filtration, evaporation, crystallisation dry gas Y dry gas Y dry gas Y dry gas Y water calcium oxide concentrated sulfuric acid calcium oxide C D A B Y Y Y Y

5 6092/01/4E/PRELIM/2024 [Turn over 7 An aqueous solution of a salt is tested and the following results are obtained. test result addition of a few drops of aqueous ammonia followed by addition of excess aqueous ammonia white precipitate forms precipitate remains addition of 2 cm3 of aqueous barium nitrate white precipitate forms What is the identity of the salt? A aluminium sulfate B calcium chloride C zinc chloride D zinc sulfate 8 A giant molecule contains a large amount of carbon-12 and carbon-13 isotopes. The average relative atomic mass of carbon in the giant molecule is 12.2. What proportion of carbon-12 atoms is present in the giant molecule? A 20% B 50% C 60% D 80% 9 Element Q has p protons and n neutrons in its nucleus. What row gives the correct number of sub-atomic particles in a positive ion of an isotope of Q? electron proton neutron A p p n + 1 B p - 1 p n - 1 C p - 1 p + 1 n D p + 1 p n

6 6092/01/4E/PRELIM/2024 10 A student made four statements about elements, compounds and mixtures. statement 1: Elements are made up of only one type of atom. statement 2: Compounds have similar properties to the elements they are made of. statement 3: Little or no energy change is involved when a compound is formed. statement 4: Mixtures have a fixed ratio of components. How many of the above statement(s) is / are correct? A one B two C three D four 11 The melting point of magnesium oxide is much higher than the melting point of sodium oxide. Which statement best explains the difference in their melting points? A Magnesium ion has more protons than sodium ion. B Magnesium is less reactive than sodium. C Sodium has a greater number of ions per formula unit in its oxide than magnesium. D Sodium ion has a smaller charge than magnesium ion. 12 The bonding in fumaric acid can be represented by the structure shown. How many electrons are involved in bonding in a molecule of fumaric acid? A 11 B 14 C 22 D 28

7 6092/01/4E/PRELIM/2024 [Turn over 13 Which statement is true about the oxides formed by carbon and silicon? A Both elements form only one oxide each with the same general formula of XO2, where X represents C or Si. B Oxides of carbon contain covalent bonds while oxides of silicon contain ionic bonds. C Oxides of carbon have a low melting point while oxides of silicon have a high melting point. D Oxides of carbon are insoluble in water while oxides of silicon are soluble in water. 14 7.5 g of an unknown hydrocarbon has a volume of 6 dm3 at room temperature and pressure. What is the molecular formula of the unknown hydrocarbon? A C2H4 B C2H6 C C3H6 D C3H8 15 Sodium carbonate is produced by strongly heating sodium hydrogencarbonate using the reaction shown. 2NaHCO3 → Na2CO3 + H2O + CO2 In an experiment, 21.0 g of sodium hydrogencarbonate produced 10.6 g of sodium carbonate. What was the percentage yield of sodium carbonate? [Mr: NaHCO3, 84; Na2CO3, 106] A 21×106 84 B 10.6 ×84 ×100 21 ×106 C 10.6 ×106 ×100 21 ×84 D 10.6 ×84 ×2 ×100 21 ×106

8 6092/01/4E/PRELIM/2024 16 A sample of lithium oxide, Li2O, is dissolved in 250 cm3 of distilled water. 25.0 cm3 of the solution is neutralised by 30.0 cm3 of 0.5 mol/dm3 dilute sulfuric acid. What is the mass of lithium oxide dissolved in 250 cm3 of distilled water? A 0.6 g B 4.5 g C 9.0 g D 18.0 g 17 The change in pH is monitored during a titration experiment between sodium