RVHS Prelim_H2_Chemistry_P2_QP

River Valley High School 9729/02/PRELIMS/25 2025 Preliminary Examination [Turn over RIVER VALLEY HIGH SCHOOL JC 2 PRELIMINARY EXAMINATION CANDIDATE NAME CLASS 2 4 J CENTRE NUMBER S INDEX NUMBER H2 CHEMISTRY 9729/02 Paper 2 Structured Questions 16 September 2025 2 hours Candidates answer on the Question Paper. Additional Materials: Data Booklet READ THESE INSTRUCTIONS FIRST Write your Centre number, index number, class and name on all the work that you hand in. Write in dark blue or black pen. You may use an HB pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. DO NOT WRITE IN ANY BARCODES. Answer all questions in the spaces provided on the Question Paper. If additional space is required, you should use the pages at the end of this booklet. The question number must be clearly shown. The use of an approved scientific calculator is expected, where appropriate. A Data Booklet is provided. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use Question Number 1 2 3 4 5 6 Marks 13 15 9 16 10 12 significant figures units Total 75 This document consists of 28 printed pages.

2 River Valley High School 9729/02/PRELIMS/25 2025 Preliminary Examination 1 (a) Fig. 1.1 shows the successive ionisation energies of an element A in Period 3. Fig. 1.1 (i) Explain why the successive ionisation energies of element A increase as shown in the graph. ……………………..………………………………………………….......... ……………………..………………………………………………….......... ……………………..………………………………………………….......... [1] (ii) Identify which group element A belongs to. Explain your reasoning. ……………………..………………………………………………….......... ……………………..………………………………………………….......... ……………………..………………………………………………….......... ……………………..………………………………………………….......... ……………………..………………………………………………….......... [2]

3 River Valley High School 9729/02/PRELIMS/25 2025 Preliminary Examination [Turn over (b) Calcium and scandium are both found in Period 4 of the Periodic Table. Explain why the atomic radius of scandium is smaller than that of calcium. ……………………………………………………………………………………... ……………………………………………………………………………………... ……………………………………………………………………………………... ……………………………………………………………………………………... ……………………………………………………………………………………... ……………………………………………………………………………………... [2] (c) Like Group 2 carbonates, the hydroxides of Group 2 elements can undergo thermal decomposition. In the process, water vapour is produced. (i) Write an equation for the decomposition of calcium hydroxide. ……………………..………………………………………………….......... ……………………..………………………………………………….......... [1] (ii) Nickel(II) hydroxide can undergo thermal decomposition similar to calcium hydroxide. Given that the atomic radius of scandium and nickel are approximately similar, deduce whether nickel( II) hydroxide would decompose a