St Gabriel 2024 Prelim Sec 4E Chemistry P1

St. Gabriel’s Secondary School 2024 ‘O’ Preliminary Examination Subject : Chemistry Paper : 6092 / 01 Level/Stream : Secondary 4 (Express) Duration : 1 hour Date : 26 August 2024 Additional Materials: 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, index number and class on the Answer Sheet in the spaces provided unless this has been done for you. 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 18. The use of an approved scientific calculator is expected, where appropriate. 2023_EYE_Sec 3N Science (Chemistry) This question paper consists of 18 printed pages. Name: …………………………………………………… ( ) Class: Sec ………………..

2 SGSS/Chemistry/P1/4E/Prelim/2024 1 The setup shown is used to collect gas produced during a chemical reaction. Which reaction is this setup best suited for? A CaCO3(s) → CaO(s) + CO2(g) B C6H5N2Cl(s) + H2O(l) → C6H5OH(aq) + N2(g) + HCl(aq) C CuSO4.5H2O(s) → CuSO4(s) + H2O(g) D Na2SO3(s) + 2HCl (aq) → 2NaCl(aq) + SO2(g) + H2O(l) 2 The table shows the Rf values for dyes P, Q, R and S in four different solvents. dye solvent ethanol propanone tetrachloromethane water P 0.91 0.72 0.58 0.34 Q 0.82 0.65 0.20 0.00 R 0.75 0.65 0.13 0.59 S 0.66 0.42 0.20 0.00 Which statement is correct? A Dye P is the most soluble in all four solvents. B Dyes Q and R are the same dye as they have the same Rf value in propanone. C Dye S is the only dye that is insoluble in water. D Ethanol is the only solvent that can be used to separate a mixture of all four dyes. 3 Weather balloons are used in the study of the climate and atmosphere. A weather balloon filled with helium gas greatly increases in volume as it goes higher up in the sky. What is a likely reason for the expansion of the balloon as it goes higher? A The distance between particles in the balloon decreases. B The distance between particles in the balloon increases. C The energy of the particles in the balloon decreases. D The energy of the particles in the balloon increases.

3 SGSS/Chemistry/P1/4E/Prelim/2024 4 Tube 1 shows the result of an experiment to investigate the formation of ammonium chloride from the reaction between ammonia gas and hydrogen chloride gas. A similar experiment was set up in Tube 2 to investigate the reaction between ammonia gas and hydrogen fluoride gas. At which position, A, B, C or D, is ammonium fluoride most likely to form? 5 How many electrons and neutrons are present in one hydroxide ion, OH–? electrons neutrons A 9 8 B 9 9 C 10 8 D 10 9 6 Element X exists as two naturally occurring isotopes, 51X and 54X. The relative isotopic abundance of 51X is 77.8%. What is the relative atomic mass of element X? A 51.7 B 51.9 C 52.5 D 53.4 cotton wool soaked in concentrated hydrochloric acid cotton wool soaked in concentrated hydrofluoric acid cotton wool soaked in aqueous ammonia solid ammonium chloride Tube 1 Tube 2 A B C D

4 SGSS/Chemistry/P1/4E/Prelim/2024 7 The setup shown is used to test if potassium chloride crystals can light up a bulb. The bulb does not light up. Distilled water is then added to the beaker and the bulb lights up. Which statement best explains this observation? A Electrons are free to move in the solution when potassium chloride dissolves. B Metal ions are free to move in the solution when potassium chloride melts. C Only metal ions are free to move in the solution when potassium chloride reacts with water. D Oppositely charged ions are free to move in the solution when potassium chloride dissolves. 8 Which pair of elements cannot be used to form an alloy? A aluminium and magnesium B copper and zinc C lead and tin D sodium and chlorine 9 The diagram shows three different substances, X, Y and Z. X Y Z Which row gives the correct classification of X, Y and Z? X Y Z A element compound element B element compound mixture C element mixture compound D compound mixture mixture bulb electrodes potassium chloride crystals beaker cell

5 SGSS/Chemistry/P1/4E/Prelim/2024 10 Which aqueous solution contains the greatest number of ions? A 1 dm3 of 0.1 mol/dm3 Al(NO3)3 B 1 dm3 of 0.2 mol/dm3 H2SO4 C 1 dm3 of 0.3 mol/dm3 MgCl2 D 1 dm3 of 0.4 mol/dm3 HCl 11 Elkinstantonite, a mineral obtained from an ancient meteorite that landed in Somalia, was found to have the following composition. iron 52.1% phosphorus 14.4% oxygen 33.5% What is its empirical formula? A Fe2PO2 B Fe2PO5 C Fe4P2O9 D Fe8P4O9 12 Iron can be extracted from its ore, Fe2O3, by reducing it with coal in a blast furnace. Fe2O3 + 3C → 2Fe + 3CO What is the percentage purity of the iron ore if 1200 g of Fe2O3 produces 250 g of iron? A 56 × 2 250 × 1200 160 × 100 B 56 250 × 2 × 160 1200 × 100 C 250 56 × 2 × 160 1200 × 100 D 250 × 2 160 × 1200 56 × 100

6 SGSS/Chemistry/P1/4E/Prelim/2024 13 The graph shows the change in pH as substance Y is added from a burette to substance X. volume of substance Y added / cm3 What could substances X and Y be? X Y A aqueous ammonia dilute ethanoic acid B aqueous ammonia dilute hydrochloric acid C aqueous sodium hydroxide dilute ethanoic acid D aqueous sodium hydroxide dilute hydrochloric acid 14 The table shows some information about the oxides of three elements, T, U and V, when added to water. oxide of T oxide of U oxide of V dissolved to form a solution of pH 2 insoluble dissolved to form a solution of pH 13 The oxide of U is white in colour. What could be the identity of T, U and V? T U V A calcium aluminium sulfur B calcium copper sulfur C sulfur aluminium calcium D sulfur copper calcium 7

7 SGSS/Chemistry/P1/4E/Prelim/2024 15 Aqueous sodium hydroxide was added from a burette to an unknown acid in a conical flask. The graph shows the change in pH of the mixture in the flask recorded during the titration. 20 volume of NaOH added / cm3 The table shows the range of colour change of some indicators. indicator pH range of colour change alizarin yellow 10.1 – 12.0 bromothymol blue 6.0 – 7.6 cresolphthalein 8.1 – 9.7 methyl red 4.4 – 6.2 Which indicators can be used for this titration? A alizarin yellow and bromothymol blue B alizarin yellow and cresolphthalein C bromothymol blue and methyl red D cresolphthalein and methyl red 16 Four students each dissolved an indigestion tablet in 100 cm3 of water before titrating 25.0 cm3 of their indigestion tablet solutions with dilute hydrochloric acid using the same indicator. The table shows the results of all four students. student 1 2 3 4 volume of HCl used / cm3 24.50 24.40 24.30 25.00 Which could be a possible error made by student 4? A The burette was rinsed with dilute hydrochloric acid solution. B The conical flask was rinsed with indigestion tablet solution. C The pipette was rinsed with dilute hydrochloric acid solution. D There were air bubbles present while pipetting indigestion tablet solution. 14 7 0 0 10 30 40 pH

8 SGSS/Chemistry/P1/4E/Prelim/2024 17 How many different soluble salts can be prepared from the list of reactants