2022 YHSS Chem Prelims P2

1 YUHUA SECONDARY SCHOOL PRELIMINARY EXAMINATION 2022 SECONDARY FOUR EXPRESS CANDIDATE NAME CLASS INDEX NUMBER CHEMISTRY 6092/02 Paper 2 25 August 2022 1 hour 45 minutes Candidates answer on the Question Paper. Setter: Ms Cerenna Ng No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name, class and index number on all the work you hand in. Write in dark blue and black pen. You may use a pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Section A Answer all questions in the spaces provided. Section B Answer all three questions, the last question is in the form either/or. Answer all questions in the spaces provided. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. A copy of the Periodic Table is printed on page 21. The use of an approved scientific calculator is expected, where appropriate. For Examiner’s Use Section A / 50 Section B / 30 Total / 80 This document consists of 21 printed pages, inclusive of this page. [Turn over

2 YHSS/Prelims/2022 Secondary Four Express Chemistry (Paper 2) Section A (50 marks) Answer all the questions in the spaces provided. 1 Deuterium is an isotope of hydrogen. The diagram shows the structure of an ion of deuterium. (a) Complete the following table to show the names and charges of the particles in this deuterium ion. symbol name charge neutron +1 −1 [1] (b) Using the symbol D to represent deuterium, give the chemical formula of (i) the ion shown above; .…......... [1] (ii) the compound formed between deuterium and sodium. .…......... [1] (c) Would you expect the oxide of deuterium to be a solid, a liquid or a gas at room temperature and pressure? Explain your reasoning. ………….…………….…………………………………….……………………………………….. ………….……………………………………………….……………………………………….. [2] [Total: 5] - - + + -

3 YHSS/Prelims/2022 Secondary Four Express Chemistry (Paper 2) [Turn Over 2 Two samples of rocks, X and Y, were tested to find out if they originated from the same region. The rock samples were crushed and a suitable acid was added to dissolve impurities in the rock samples. The resulting solutions from the mixtures were chromatographed, together with five known metal ions. The diagram shows the chromatograms after spraying with a locating agent. (a) State why a locating agent was used. …………….…………….……………………..…………….……………………………………… …………...…………………………………..………….………………………………………..[1] (b) Deduce if the two samples of rock were from the same region. Give a reason for your answer. …………….…………….……………………..…………….……………………………………… …………….…………….……………………..…………….……………………………………… …………….…………….……………………..……………