Chem S3 EOY PLMGS P1 2023 with ans

1 CANDIDATE NAME CLASS CLASS INDEX NUMBER CHEMISTRY Modified 6092/01 Paper 1 Multiple Choice 4 October 2023 Additional Materials: Multiple Choice Answer Sheet 45 minutes READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name and class index number on the separate Answer Sheet in the spaces provided. There are thirty 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 2. The use of an approved scientific calculator is expected, where appropriate. This paper consists of 14 printed pages, including this cover page. Paya Lebar Methodist Girls’ School (Secondary) End of Year Examination 2023 Secondary 3 Express [Turn over

3 1 “Particles moving very slowly from an area of higher concentration to an area of lower concentration.” Which process is being described? A a liquid freezing B a solid melting C a substance diffusing through a liquid D a substance diffusing through a gas 2 Diagrams of the three states of matter for carbon dioxide are shown below. Which two diagrams show the states of matter before and after the sublimation of carbon dioxide? A 2 to 1 B 3 to 1 C 2 to 3 D 3 to 2 3 The table shows information about four different particles. What are the values of W, X, Y and Z? [Turn over

4 4 An atom of one isotope of bromine is represented by the symbol 𝐵𝑟.35 81 Which row is correct for an atom of a different isotope of bromine? number of neutrons number of protons nucleon number A 44 35 44 B 79 44 79 C 44 35 79 D 47 35 82 5 Two elements, P and Q are in the same period of the Periodic Table. P and Q react together to form an ionic compound. Part of the lattice of this compound is shown. Which statement is correct? A An ion of P has more electrons than an ion of Q. B P is to the left of Q in the Periodic Table. C Element P is non-metallic. D The formula of the compound is P4Q4. 6 Iron is a metal. Its structure consists of a giant lattice of positive ions in a ‘sea of electrons’. Which statements about solid iron are correct? 1 Iron conducts electricity because the electrons are free to move. 2 Iron conducts heat because the positive metal ions are free to move. 3 Iron has a high melting point due to the strong ionic bonds. 4 Iron is malleable because the layers of atoms can slide over one another. A 1 and 3 B 1 and 4 C 2 and 3 D 1, 2 and 4

5 7 The diagram shows the structure of silicon carbide, a compound of carbon and silicon. Which are the most likely properties of silicon carbide? melting point/0C boiling point/0C soluble in water conducts electricity A - 120 - 60 yes no B 560 988 no yes C 875 1242 yes no D 1623 2475 no no 8 The arrangement of atoms in pure copper is shown below. Brass can be made by adding zinc to pure copper. Which description of the arrangement of atoms in brass is correct? A A regular pattern of copper atoms with zinc atoms fitting into one corner. B A regular pattern of zinc atoms with copper atoms fitting into the gaps between them. C Rows of copper atoms alternating with rows of zinc atoms. D An irregular pattern of zinc atoms and copper atoms randomly spread throughout the structure. [Turn over

6 9 The structure of methanal is shown below. Which diagram shows the arrangement of outer shell electrons in a molecule of methanal? 10 A student measures the time taken to react 2 g of magnesium with 50 cm3 of sulfuric acid. Which apparatus is essential to complete the experiment? 1 stopwatch 2 thermometer 3 measuring cylinder 4 electronic balance A 1, 3 and 4 B 1, 2 and 4 C 3 and 4 D 1 and 3

7 11 A paper chromatography experiment is carried out to find an R f value for Fe 3+(aq). The result is shown below. To make the spot containing Fe3+ (aq) more visible, the spot is sprayed with aqueous sodium hydroxide so that a precipitate of iron (III) hydroxide forms. Under the conditions of the experiment, the Rf of Fe3+ (aq) is given by ….1… and the colour of the precipitate is …2… Which row correctly completes 1 and 2? 1 2 A 𝑥 𝑦 green B 𝑧 𝑦 red-brown C 𝑦 𝑥 green D 𝑥 𝑦 red-brown 12 Which sequence of procedures is used to separate a pure, dry sample of hydrated copper (II) sulfate, CuSO4.5H2O, from a mixture containing hydrated copper (II) sulfate and calcium carbonate, CaCO3? A dissolve in water → filtration → evaporation to dryness B dissolve in water → filtration → crystallisation C distillation → crystallisation → heating to remove all water D fractional distillation → filtration → heating to remove all water z [Turn over

8 13 When iron reacts with dilute hydrochloric acid, hydrogen is formed. Due to the presence of impurities in the iron, some hydrogen sulfide gas is also formed. Hydrogen sulfide gas is soluble in water. Water vapour can be removed from a mixture of gases using concentrated sulfuric acid. Which diagram shows the apparatus suitable to prepare a pure, dry sample of hydrogen?

9 14 The rate of reaction between magnesium and dilute hydrochloric acid is investigated. The equation is shown. Mg (s) + 2HCl (aq) → MgCl2 (aq) + H2 (g) A known mass of magnesium is added to an excess of dilute hydrochloric acid. The concentration of the hydrochloric acid and the volume of hydrogen produced is measured at regular time intervals. Which pair of graphs correctly shows the experimental results? [Turn over

10 15 Which statement about acids and bases is correct? A A 0.1 mol/dm3 solution of ethanoic acid has a higher pH than a 0.1 mol/dm3 solution of hydrochloric acid. B All bases dissolve in water to produce OH- ions. C All bases react with nitrates to produce ammonia. D Oxides of metals are always acidic in character. 16 Which substance reacts with dilute sulfuric acid in the preparation of a pure sample of lead (II) sulfate? A lead foil B powdered lead (II) carbonate C powdered lead (II) oxide D aqueous lead (II) nitrate 17 Two solutions are prepared. Solution P is 0.0500 mol/dm3 hydrochloric acid. Solution Q is 0.0500 mol/dm3 butanoic acid. A 2 cm strip of magnesium is added into 100 cm3 of each solution. Fizzing is seen in both solutions but the fizzing is faster in solution P than it is in solution Q. Which statement helps to explain this observation? A Magnesium reacts with solution P to form a salt but does not form a salt with solution Q. B More acid particles are dissociated in solution P than are dissociated in solution Q. C Solution Q contains a stronger acid than solution P. D The particles are closer together in solution Q than they are in solution P. 18 Tin oxide is an amphoteric oxide. Which reagent can be used to distinguish between tin oxide from calcium oxide? 1 HNO3 (aq) 2 HCl (aq) 3 NH3 (aq) 4 NaOH (aq) A 1 or 2 B 1 or 3 C 2 or 4 D 3 or 4

11 19 The diagrams show thre