2026 SCGS P1 2 with ans

1 CANDIDATE NAME CLASS 4 INDEX NUMBER CHEMISTRY 6092/01 Paper 1 Multiple Choice 28 August 2026 1 hour 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, class and register number on the Answer Sheet in the spaces provided. There are forty questions in this paper. Answer all questions. For each question, there are four possible answers, A, B, C, 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 question paper consists of 15 printed pages and 1 blank page. SINGAPORE CHINESE GIRLS’ SCHOOL PRELIMINARY EXAMINATION SECONDARY FOUR

2 1 A student investigates the rate of reaction between a solid and a liquid. During the reaction, the student measures the volume of gas released. The student is provided with a conical flask, a pipette and a balance. Which additional apparatus is needed? 1 stopwatch 2 gas syringe 3 thermometer A 1 and 2 B 1 and 3 C 1 only D 2 only 2 A student set up the apparatus as shown below to collect a sample of clean, dry gas X. What is gas X and what is a suitable drying agent? gas X drying agent A ammonia calcium oxide B ammonia concentrated sulfuric acid C hydrogen chloride calcium oxide D hydrogen chloride concentrated sulfuric acid 3 In addition to sodium ions and chloride ions, sea water contains sulfate ions. Which method could be used to measure the amount of sulfate ions present in a sample of sea water? A add excess aqueous lead(II) nitrate, dry and weigh the precipitate formed B add excess aqueous barium nitrate, dry and weigh the precipitate formed C evaporate off all the water and weigh the remaining solid D measure the electrical conductivity of the sample dry sample of gas X drying agent mixture of ammonium chloride and calcium hydroxide heat

3 4 Which statement about Rf values in paper chromatography is correct? A The unit for Rf value is the centimetre. B When the length of the paper is doubled, Rf value is also doubled. C Rf value is calculated as distance moved by solventdistance moved by spot . D The maximum possible Rf value is 1. 5 Which statement is correct? A Copper conducts electricity but brass does not. B Copper is metal but brass is a non-metal. C Copper is an element but brass is a compound. D Copper is a pure substance but brass is a mixture. 6 In which process is energy released overall2? A photosynthesis B respiration C fractional distillation of crude oil D electrolysis of water to form hydrogen and oxygen 7 The following all contain covalent bonds. 1 methane 2 carbon dioxide 3 propene Which contain at least one double covalent bond? A 1 and 2 B 2 and 3 C 2 only D 3 only 8 Which gas diffuses most rapidly? A propane molecules at 25 °C B propene molecules at 25 °C C propane molecules at 75 °C D propene molecules at 75 °C

4 9 What is observed when aqueous hydrochloric acid is added to aqueous silver nitrate? A no observable change B yellow precipitate C white precipitate D effervescence 10 Aluminium oxide has the formula Al2O3. Which statements about aluminium oxide are correct? 1 5.29 kg of aluminium can be extracted from 10 kg of aluminium oxide. 2 Pure aluminium oxide contains a higher mass of oxygen than of aluminium. 3 1 mole of aluminium oxide weighs 102 g. A 1 and 3 B 2 and 3 C 2 only D 3 only 11 Barium hydroxide reacts with hydrochloric acid according to the equation shown. Ba(OH)2(aq) + 2HCl(aq) → BaCl2(aq) + 2H2O(l) A solution containing 0.015 mol of barium hydroxide is added to a conical flask. The aqueous barium hydroxide is titrated with 1.50 mol/dm3 hydrochloric acid from a burette. Which volume of hydrochloric acid is needed to give a neutral solution? A 10.00 cm3 B 15.00 cm3 C 20.00 cm3 D 30.00 cm3 12 Hydrogen gas reacts with oxygen gas to form steam as shown in the chemical equation. 2H2(g) + O2(g) → 2H2O(g) Which statement about the reacting ratios is incorrect? (All statements assume that the reactants are at the same temperature and pressure.) A 2 molecules of hydrogen react with 1 molecule of oxygen. B 2 moles of hydrogen react completely with 1 mole of oxygen. C 2 g of hydrogen gas reacts completely with 1 g of oxygen gas. D 2 cm3 of hydrogen gas reacts completely with 1 cm3 of oxygen gas.

5 13 X and Y are oxides of two different elements. • X reacts with water to produce aqueous solution Z. • Z turns universal indicator paper violet. • An aqueous solution of Y reacts with sodium carbonate to produce carbon dioxide gas. Which statement is correct? A X and Y are both the oxides of metals. B X and Y are both the oxides of non-metals. C X is the oxide of a metal and Y is the oxide of a non-metal. D X is the oxide of a non-metal and Y is the oxide of a metal. 14 A sample of 2.0 g of zinc granules is reacted with an excess of 2.0 mol/dm3 hydrochloric acid. The volume of hydrogen produced over time is measured. The results are plotted to give graph 1. Which graph (A, B, C, or D) would be produced when 2.0 g of zinc granules is reacted with an excess of 2.0 mol/dm3 sulfuric acid under the same conditions?

6 15 Two methods used by students to measure the rate of a reaction are the ‘disappearing cross’ method and the ‘loss of mass’ method. • For the ‘disappearing cross’ method, the student measures the time taken for the cross to be covered by the precipitate formed. • For the ‘loss of mass’ method, the student measures the loss of mass over a known time interval. The rates of two reactions are investigated. • reaction 1: Warm aqueous silver nitrate is added to chlorobutane dissolved in ethanol. Two products are formed. One is an organic compound which is soluble in ethanol and the other is silver chloride. • reaction 2: Pieces of solid calcium carbonate are added to dilute hydrochloric acid. Which method should be used for each reaction? reaction 1 reaction 2 A disappearing cross disappearing cross B disappearing cross loss of mass C loss of mass disappearing cross D loss of mass loss of mass 16 Four different solutions were electrolysed in separate experiments. In one of the experiments, element X2 was formed at the positive electrode. 2X¯ → X2 + 2e¯ Which combination of solution and electrodes produces X2 as shown by the equation above? A aqueous silver nitrate with silver electrodes B aqueous copper(II) nitrate with inert electrodes C concentrated aqueous sodium chloride with inert electrodes D dilute aqueous sodium chloride with inert electrodes

7 17 The diagram shows a set-up used to purify copper. The masses of the electrodes at the start and end of the process are recorded in the table below. What is the percentage of pure copper found in the sample of impure copper? mass of electrode impure copper / g pure copper / g at the start 30.0 20.0 at the end 0.0 25.0 A 16.7% B 66.7% C 80.0% D 83.3% 18 Calcium carbonate decomposes to form calcium oxide and carbon dioxide. The energy profile diagram is shown. Which statement about this energy profile is incorrect? A The activation energy in this reaction is labelled y. B The energy absorbed in forming bonds is labelled z. C