ADSS Prelim P1

This question paper consists of 19 printed pages including this cover page. ADMIRALTY SECONDARY SCHOOL SUBJECT : Chemistry CODE/PAPER : 6092/1 LEVEL/STREAM : Secondary 4 Express DATE : 26 August 2024 TIME : 0800h – 0900h DURATION : 1 hour 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 Optical Answer Sheet 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 Optical Answer Sheet. Fill in the Optical 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 19. The use of an approved scientific calculator is expected, where appropriate. DO NOT TURN OVER THIS PAPER UNTIL YOU ARE TOLD TO DO SO. PRELIMINARY EXAMINATION 2024 NAME: NO: CLASS: 40

2 1 A student sets up the apparatus as shown below. What gas will be collected from the set-up shown and what would be a suitable dehydrating agent? name of gas dehydrating agent A ammonia gas concentrated sulfuric acid B ammonia gas calcium oxide C hydrogen chloride concentrated sulfuric acid D hydrogen chloride calcium oxide 2 A bottle of magnesium carbonate has been contaminated with sodium chloride. How can pure magnesium carbonate be obtained from this mixture? A Add acid to the mixture, filter then evaporate the filtrate. B Add acid to the mixture, filter then collect the residue. C Add water to the mixture, filter then evaporate the filtrate. D Add water to the mixture, filter then collect the residue. 3 Which piece of apparatus could be used to determine the end-point of the reaction between hydrochloric acid and potassium hydroxide? A electronic balance B gas syringe C stopwatch D thermometer

3 4 Which of the following best describes the particles present in a diluted solution of potassium chloride? potassium chloride ions water molecules A far apart close together B close together close together C close together far apart D far apart far apart 5 In a porous pot experiment, the porous pot was placed in a beaker of nitrogen. The porous pot was joined to a U tube filled with mercury as shown. Which of the gases, 1 to 4, when used to fill the porous pot would cause level A to move down? 1 ammonia 2 carbon dioxide 3 chlorine 4 hydrogen A 1 and 3 only B 1 and 4 only C 2 and 3 only D 2 and 4 only level A nitrogen mercury U-tube porous pot

4 Diagram A Diagram B