2026 SJI P1 2 with ans

ST JOSEPH’S INSTITUTION PRELIMINARY EXAMINATION 2026 (YEAR 4) CANDIDATE NAME CLASS INDEX NUMBER CHEMISTRY Paper 1 Additional Materials: Multiple Choice Answer Sheet 6092/01 31 August 2026 1 hour (08:05 – 09:05) 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. 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 Question paper. A copy of the Periodic Table is printed on page 18. The use of an approved scientific calculator is expected, where appropriate. This document consists of 18 printed pages. [Turn Over

2 1 Gas Y is less dense than air, soluble in water, and turns Universal Indicator solution blue. Which method is most suitable for collecting a dry sample of gas Y? A B C D 2 Three processes are listed below. 1 obtaining solid copper(II) sulfate salt from copper(II) sulfate solution 2 obtaining water from sodium chloride solution 3 separating iodine from a mixture of iodine and nickel Which separation technique should be used for each process? 1 2 3 A crystallisation distillation sublimation B crystallisation filtration magnetic attraction C evaporation distillation sublimation D evaporation filtration magnetic attraction dry Y water Y Y dry Y calcium oxide dry Y calcium oxide Y Y dry Y concentrated sulfuric acid

3 3 A student separated a mixture of two alkanes, hexane (boiling point = 69 °C) and heptane (boiling point = 98 °C), using the apparatus shown. Which change would improve the separation of the two alkanes? A add boiling chips to the round-bottomed flask B heat the mixture directly with a Bunsen burner C reverse the direction of water flow through the condenser D use smaller glass beads in the fractionating column 4 The chromatogram obtained from a paper chromatography experiment is shown below. The chromatogram is not drawn to scale. Given that the Rf value of dye P is 0.40, calculate the Rf value of dye Q. A 0.50 B 0.60 C 0.70 D 0.80 thermometer hot water bath hexane and heptane mixture cold water in cold water out beaker glass beads dye Q dye P solvent front 1.80 cm 3.15 cm start line

4 5 A sample of a pure substance was heated until it became completely gaseous. The heating curve obtained is shown below. Which statement best describes what happens to the particles during Stage B? A The particles change from an orderly arrangement to a disorderly arrangement. B The particles change from sliding over one another to vibrating in fixed positions. C The particles gain kinetic energy and move more quickly and randomly. D The particles take in energy to overcome the forces of attraction between them. 6 Which diagram represents a mixture of compounds? A B C D 7 Which of the following has the same number of electrons as a sulfide ion, S2-? A chlorine atom B fluorine molecule C hydroxide ion D magnesium ion A temperature / °C time / min 50 65 B C

5 8 Asbestos is a naturally occurring mineral commonly used in building materials due to its strength and resistance to heat. The diagram below shows a simplified structure of asbestos. Which types of chemical bonds are present in the structure of asbestos? 1 covalent bonds 2 intermolecular forces of attraction 3 ionic bonds 4 metallic bonds A 1, 3 and 4 only B 1 and 2 only C 1 and 3 only D 2 and 4 only 9 Elements Y and Z form an ionic compound of formula YZ2. What could the proton numbers of Y and Z be? Y Z A 7 3 B 11 8 C 12 9 D 16 17

6 10 What is the total number of atoms present in 12 dm3 of ammonia gas? A 1.20 x 1021 B 3.01 x 1023 C 6.02 x 1023 D 1.20 x 1024 11 0.84 g of magnesium carbonate reacts with 25 cm³ of 1.0 mol/dm3 hydrochloric acid. MgCO3 + 2HCl → MgCl2 + CO2 + H2O What is the maximum mass of magnesium chloride that can be produced? [Mr: MgCO3, 84; HCl, 36.5; MgCl2, 95] A 0.95 g B 1.19 g C 1.90 g D 2.38 g 12 A 60 g alloy containing zinc and copper is added to excess dilute sulfuric acid. A total of 18 dm3 of hydrogen gas is collected at room temperature and pressure. What is the percentage by mass of zinc in the alloy? A 19 % B 41 % C 50 % D 81 % 13 Which pair of oxides both react with aqueous sodium hydroxide? A aluminium oxide and phosphorus trioxide B calcium oxide and zinc oxide C copper(II) oxide and sulfur dioxide D magnesium oxide and sulfur dioxide

7 14 The graph shows how the pH changes as 0.1 mol/dm3 aqueous sodium hydroxide is gradually added to 0.1 mol/dm3 dilute ethanoic acid. The table below shows the colour change of s ome indicators and the pH range over which each colour change occurs. indicator colour change pH at which colour change occurs crystal violet yellow to violet 0.0 to 2.0 indigo carmine blue to yellow 11.4 - 13.0 methyl orange red to yellow 3.1 - 4.4 phenolphthalein colourless to pink 8.3 - 10.0 Which indicator is most suitable for determining the end-point of this titration? A crystal violet B indigo carmine C methyl orange D phenolphthalein 15 Which salts are all prepared by titration? A aluminium nitrate, iron(III) chloride, zinc sulfate B ammonium nitrate, potassium chloride, sodium nitrate C calcium nitrate, copper(II) sulfate, magnesium chloride D lithium sulfate, iron(II) chloride, lead(II) sulfate pH volume of sodium hydroxide used / cm3

8 16 Which pair of substances is most suitable for preparing a pure, dry sample of silver chloride? A silver carbonate and hydrochloric acid B silver hydroxide and sodium chloride C silver nitrate and hydrochloric acid D silver metal and hydrochloric acid 17 The flow chart below shows a series of tests carried out on solid P. Which statement is correct? A P can react with dilute sulfuric acid to produce solution R. B Q is the metal present in P that is unaffected by heating. C R is a green solution. D R reacts with excess aqueous sodium hydroxide to form a dark blue solution. 18 The results of tests carried out on an aqueous solution of compound X are shown below. test observation aqueous ammonia white precipitate, insoluble in excess aqueous sodium hydroxide white precipitate, soluble in excess acidified barium nitrate white precipitate acidified silver nitrate no visible observation What is the identity of compound X? A aluminium chloride B aluminium sulfate C zinc chloride D zinc sulfate green solid P black solid Q + carbon dioxide solution R dark blue solution heat excess aqueous ammonia sulfuric acid

9 19 Which of the following compounds contains two different elements that have identical oxidation states? A HClO B Mg(OH)2 C Na2SO4 D NH4Cl 20 A compound decolourises acidified potassium manganate(VII). What could this compound be? 1 magnesium nitrate 2 iron(II) chloride