2023 CCHS(M) Chem Prelims P1

[Turn over Name: Class: Class Register Number: Parent’s Signature ______________________ PRELIMINARY EXAMINATION 2023 SECONDARY 4 CHEMISTRY 6092/01 Paper 1 Multiple Choice September 2023 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 clearly in the spaces provided at the top of this page. 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 booklet. 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.

2 2023 Preliminary Exam/CCHMS/Secondary 4/Chemistry/6092/01 1 A student accidentally mixed 50 cm3 of oil and 5 g of solid calcium nitrate. Which sequence of separation would allow him to obtain pure samples of oil and solid calcium nitrate most easily? A Filtration followed by washing the residue with water. B Add water with stirring, use a separating funnel followed by crystallisation. C Simple distillation followed by crystallisation. D Use a separating funnel, chromatography followed by crystallisation. 2 The rate of diffusion of nitrogen and ammonia gases were compared at 50 oC and 25 oC. Which would have the slowest rate of diffusion? A Nitrogen gas at 50 oC. B Nitrogen gas at 25 oC. C Ammonia gas at 50 oC. D Ammonia gas at 25 oC. 3 An aqueous solution containing two salts is found. A series of tests is carried out to identify the ions present. The results are shown. test observations Add dilute nitric acid followed by aqueous lead(II) nitrate. No effervescence and white precipitate is observed. Add aqueous sodium hydroxide followed by warming. White precipitate is formed and dissolves in excess sodium hydroxide to form a colourless solution. No effervescence is observed. Add aluminium foil followed by warming. Effervescence is observed and gas turns moist red litmus paper blue. Add aqueous ammonia. White precipitate is formed. The mass of the white precipitate decreases by half when excess ammonia is added. Which of the following salts are present in the aqueous solution? A zinc sulfate and aluminium nitrate B zinc sulfate and calcium nitrate C ammonium chloride and aluminium sulfate D calcium chloride and ammonium sulfate

3 [Turn over 2023 Preliminary Exam/CCHMS/Secondary 4/Chemistry/6092/01 4 Three particles and their nuclide notations are shown. Particle 1 2 3 Nuclide notation X Y