NYJC 2025 H2 Chem prelim 9729 QP (updated for 2026 syallbus)

[Turn Over This document consists of 15 printed pages. NANYANG JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION Higher 2 CHEMISTRY 9729/01 Paper 1 Multiple Choice 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, CT and NRIC / FIN on the Answer Sheet in the spaces provided. There are thirty questions in 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. H

2 H2 Chemistry 9729/01 NYJC J2/2025 PRELIM 1 X is a transition element that forms ions of various oxidation states. One ion, X 2+, reduces Cr2O72− in acid solution. If 1 mol of Cr2O72− is reduced by 2 mol of X 2+, which of the following species is formed in the reaction? A XO42− B 1 XO2+ C XO2+ D X3+ 2 M and T are cations. M contains n protons and has a charge of 3+. T contains (n–2) protons and has the same number of electrons as M. What is the formula of the oxide formed by T? A TO B T2O C T2O3 D TO2 3 The boiling point of methane is −161.5 oC while that of neon is −264 oC. Why is the boiling point of methane greater than that of neon? A Molecules of methane have a larger surface area to form stronger intermolecular forces than those of neon B A molecule of methane has more electrons than an atom of neon. C A molecule of methane has a greater relative molecular mass than an atom of neon. D Molecules of methane form hydrogen bonds, but those of neon do not. 4 Boron trifluoride is a highly reactive gas at room temperature and hence it is difficult to handle. To store it in liquid form, 2 mol of BF3 reacts with 1 mol of CH3CH2OCH2CH3 to form compound N. Which of the following statements is correct? A The boron atom in compound N has an incomplete octet. B 2 mol of AlF3 can also react with 1 mol of CH3CH2OCH2CH3 to form a similar compound. C Two dative bonds are formed from the boron atom in two BF3 molecules towards the O atom in CH3CH2OCH2CH3. D The bond angle with respect to boron atom in BF3 is bigger than the bond angle with respect to boron in compound N.

3 H2 Chemistry 9729/01 NYJC J2/2025 PRELIM 5 Which pairs of ions give an ionic compound with the lowest melting point? cation anion A P CH3 CH3 CH3 CH3 S O O O O B P CH2CH3 CH3CH2 CH2CH3 CH2CH3 S O O CH3 O C P CH3 CH3 CH3 CH3 S O O CH3 O D P CH2CH3 CH3CH2 CH2CH3 CH2CH3 S O O O O 6 When aqueous copper (II) sulfate is mixed with potassium iodide, a white precipitate in a brown solution is formed. The brown solution is decolori sed when aqueous sodium thiosulfate is added to it. What is the formula and the electronic configuration of the copper cation in the white precipitate? formula of white precipitate electronic configuration of the copper cation A CuI2 1s2 2s2 2p6 3s2 3p6 3d9 B CuI2 1s2 2s2 2p6 3s2 3p6 3d7 4s2 C CuI 1s2 2s2 2p6 3s2 3p6 3d10 D CuI 1s2 2s2 2p6 3s2 3p6 3d9 4s1

4 H2 Chemistry 9729/01 NYJC J2/2025 PRELIM 7 The volumes and pressures of equal masses of four gaseous compounds H2O, CH4, C16H32O2 and I2, are separately investigated, at constant temperature. The results are plotted on a graph of pV against V. Which of the following plot shows the result for CH4? 8 Which graph corresponds to the combustion of liquid ethanedioic acid, (COOH)2 at room temperature? (COOH)2(l) + ½O2(g) → 2CO2(g) + H2O(l) A B C D G / kJ mol–1 T / K 0 G / kJ mol–1 T / K 0 G / kJ mol–1 T / K 0 G / kJ mol–1 T / K 0

5 H2 Chemistry 9729/01 NYJC J2/2025 PRELIM 9 When equal volumes of 1.00 mol dm −3 hydrochloric acid and v mol dm−3 of sulfuric acid were separately neutralised by excess dilute sodium hydroxide, the heat liberated was 2a kJ and a kJ respectively. What is the concentration, v, of the sulfuric acid? A 0.25 mol dm−3 B 0.50 mol dm−3 C 1.00 mol dm−3 D 2.00 mol dm−3 10 Consider the following reaction. 3R + S → R3S The mechanism involves the following steps: Step 1: 2R R2 Step 2: R2 + S → R2S Step 3: R2S + R → R3S The overall kinetics is found to be third order. Based on the information, which is the slow step in the mechanism? A Step 1 B Step 2 C Step 3 D None of the above

6 H2 Chemistry 9729/01 NYJC J2/2025 PRELIM 11 The kinetics of the reaction below were studied using the initial rate method. I–(aq) + ClO–(aq) ⎯⎯⎯→ IO–(aq) + Cl–(aq) experiment initial [I–] / mol dm–3 initial [ClO–] / mol dm–3 initial [OH–] / mol dm–3 initial rate / mol dm–3 s–1 1 0.0013 0.012 0.100 9.4 × 10–3 2 0.0026 0.012 0.100 18.7 × 10–3 3 0.0013 0.018 0.100 14.0 × 10–3 4 0.0026 0.018 0.050 c The unit of k is found to be s−1. Which statements are correct? 1 The order of reaction with respect to [OH−] is −1. 2 OH− functions as a catalyst in this reaction. 3 The value of c is 56.0 × 10–3. A 1, 2 and 3 B 1 and 3 only C 2 and 3 only D 3 only 12 Consider the equilibrium 3P2(g) + 2OP(g) 2OP4(g). When 4 mol of OP4 was put into a 2 dm 3 container and heated, the equilibrium mixture contained 0.8 mol of OP. What is the numerical value of the equilibrium constant, Kc? A 74.1 B 9.26 C 0.108 D 0.0135 OH–

7 H2 Chemistry 9729/01 NYJC J2/2025 PRELIM 13 Due to its radioactive nature, the properties of astatine, At, have to be predicted based on its position in the Periodic Table. Which of the predictions concerning At or its compounds is correct? A Hydrogen astatide has a higher decomposition temperature than hydrogen bromide. B Astatine is a light coloured solid at room temperature. C Silver astatide is soluble in NH3(aq). D Astatine is a weaker oxidising agent than iodine. 14 The graph below shows the variation in the boiling point for 8 consecutive elements in the Periodic Table, all with atomic number less than 21. Which statements are correct? 1 The chloride of E reacts with aqueous sodium hydroxide to give a precipitate which is soluble in excess sodium hydroxide. 2 The oxide of F is neutral in aqueous solution. 3 The oxide of K dissolves readily in water to give a strongly alkaline solution. A 1, 2 and 3 B 1 and 2 only C 2 and 3 only D 1 only E K G F boiling point H I J L atomic number

8 H2 Chemistry 9729/01 NYJC J2/2025 PRELIM 15 The values of solubility products at 25 oC of three metal sulfides are shown in the table below. Hsoln of these metal sulfides is endothermic. compound value of Ksp ZnS 1.1 × 10−21 CuS 6.3 × 10−36 Ag2S 6.0 × 10−51 Which statements are correct? 1 Addition of S2− to the solution of Bi2S3 decreases the Ksp of Bi2S3. 2 Ag2S is more soluble than CuS. 3 Given a solution with [Cu2+] = [Zn2+], CuS is precipitated out first on addition of S2−. A 1, 2 and 3 B 1 and 2 only C 2 and 3 only D 3 only 16 25.0 cm3 of a 0.1 mol dm −3 monoprotic base, U, was titrated with a 0.1 mol dm −3 HCl and the following titration graph was obtained. Which statements about the above graph are correct? 1 When 25.0 cm3 of HCl is added, the pH of the resulting solution is < 7. 2 Methyl orange is a suitable indicator fo