2022 PLMGS Chem Prelims P1

1 [Turn over CANDIDATE NAME CLASS CLASS INDEX NUMBER CENTRE NUMBER INDEX NUMBER CHEMISTRY 6092/01 Paper 1 Multiple Choice 26 August 2022 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 class index number on the separate 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. 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 paper. A copy of the Periodic Table is printed on page 2. The use of an approved scientific calculator is expected, where appropriate. This document consists of 17 printed pages, including the cover page. Paya Lebar Methodist Girls’ School (Secondary) Preliminary Examination 2022 Secondary 4 Express

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4 Use the following information to answer Questions 1 and 2. When solid hydrated barium hydroxide is added to a known quantity of solid ammonium chloride, the temperature of the mixture decreases. The chemical reaction is represented by the balanced chemical equation shown below. Ba(OH)2.8H2O (s) + 2NH4Cl (s) 2NH3 (g) + 10H2O (l) + BaCl2 (s) 1 An experiment is designed to measure the temperature change when all the solid hydrated barium hydroxide reacts with the ammonium chloride. The following pieces of apparatus are available. 1 gas syringe 2 stopwatch 3 balance 4 Styrofoam cup Other than a thermometer, which piece(s) of apparatus is(are) likely needed for this experiment? A 1, 2 and 3 only B 1 and 2 only C 3 and 4 only D 4 only 2 Which diagram shows the correct way of drying and collecting the gas produced? A B C D gas concentrated sulfuric acid calcium oxide gas gas concentrated sulfuric acid calcium oxide water gas

5 [Turn over 3 A solution of X is added to 1 cm3 of sulfuric acid. Effervescence is seen. The gas produced is bubbled into a test tube of limewater. The following observation is made. What could X be? A barium carbonate B sodium hydroxide C barium nitrate D sodium carbonate white precipitate limewater

6 4 The apparatus shown is used to distil pentanol (boiling point 138 oC) from a mixture of water and pentanol. Which graph shows the change in concentration of the pentanol in flask F as the distillation proceeds? A B C