2025 ASRJC Prelim H2Chem P1_QP

9729/01/H2 [Turn over ANDERSON SERANGOON JUNIOR COLLEGE 2025 JC2 PRELIMINARY EXAMINATION NAME:______________________________ ( ) CLASS: 25 /____ CHEMISTRY 9729/01 Paper 1 Multiple Choice 2 September 2025 1 hour Additional Materials: Multiple Choice Answer Sheet Data Booklet 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 Answer Sheet. There are thirty 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. The use of an approved scientific calculator is expected, where appropriate. This document consists of 15 printed pages and 1 blank page. Multiple Choice Answer Sheet Write your name, class and NRIC / FIN number, including the reference letter. Shade the NRIC / FIN number. Exam Title: JC2 PRELIM Exam Details: H2 Chemistry / Paper 1

2 9729/01/H2 1 Sodium azide, NaN3 is an explosive used to inflate airbags in cars when they crash. It consists of positive sodium ions and negative azide ions. What are the number of electrons in the sodium ion and the azide ion? sodium ion azide ion A 10 20 B 10 22 C 12 20 D 12 22 2 The graph shows the variation of the first ioni sation energy with proton number for some elements. The letters used are not the actual symbols for the elements. Which statement about the elements is correct? A P and X are in the same period in the Periodic Table. B The general increase from Q to X is due to increasing atomic radius. C The small decrease from R to S is due to decreased shielding. D The small decrease from U to V is due to repulsion between paired electrons. first ionisation energy / kJ mol–1 proton number

3 9729/01/H2 [Turn over 3 The table identifies the shape and polarity of four molecules. Which row is correct? molecule molecular shape polarity A boron trichloride trigonal pyramidal polar B nitrogen trichloride trigonal planar non-polar C sulfur dioxide bent polar D trichloromethane tetrahedral non-polar 4 The element tin exists in two forms, grey tin and white tin. Some properties of grey tin and white tin are shown. grey tin white tin boiling point 2543 oC 2533 oC electricial conductivity none in solid or liquid good in solid and liquid malleability brittle malleable Which structural change might take place when grey tin changes to white tin? A giant covalent to giant ionic B giant cov