ACJC_Chemistry_H2 P1 Prelims

ANGLO-CHINESE JUNIOR COLLEGE DEPARTMENT OF CHEMISTRY Preliminary Examinations CHEMISTRY 9746/01 Higher 2 Paper 1 Multiple Choice 26 August 2008 1 hour Additional Materials: Multiple Choice Answer Sheet Soft clean eraser Soft pencil (type B or HB is recommended) D a t a B o o k l e t READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, Centre number and candidate number on the answer sheet in the spaces provided unless this has been done for you. There are forty 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. This document consists of 17 printed pages. 9746/01/Prelim/08 ANGLO-CHINESE JUNIOR COLLEGE © ACJC 2008 Department of Chemistry [Turn over

2 Section A For each question there are four possible answers, A, B, C, and D. Choose the one you consider to be correct. 1 In an experiment, Mn2+ ions are oxidised by S2O8 2− to form MnO4 − according to the following equation. 2Mn2+(aq) + 5S2O8 2−(aq) + 8H2O(l) → 2MnO4 −(aq) + 10SO4 2−(aq) +16H+(aq) What volume of 0.100 mol dm -3 solution of acidified Mn 2+ is required to reduce completely 25.0 cm3 of 0.200 mol dm-3 of Na2S2O8 solution? A 10 cm3 B 20 cm 3 C 30 cm 3 D 50 cm 3 2 In an experiment, 50 cm 3 of a 0.1 mol dm –3 solution of a metallic salt reacted exactly with 25 cm3 of 0.1 mol dm-3 aqueous sodium sulphite. The half equation for the oxidation of the sulphite ion is shown below. SO3 2–(aq) + H2O(l) → SO4 2–(aq) + 2H+(aq) + 2e– If the original oxidation number of the metal in the salt was +3, what would be the final oxidation number of the metal? A 0 B +1 C +2 D +4 3 10 cm 3 of a pure hydrocarbon was completely burned in 80 cm 3 of oxygen (an excess) at 425K. After cooling to room temperature, the volume of the gaseous mixture decreased by 105 cm 3 to 55 cm3. A further reduction of 40 cm3 was observed when the residual gas was passed through calcium hydroxide. All gas volumes were measured at the same temperature and pressure. What is the formula of the hydrocarbon? A C 2H6 B C 3H8 C C 4H10 D C 5H12 4 Which of the following electronic configurations represents an element that forms a simple ion with a charge of -3? A 1s2 2s2 2p6 3s2 3p1 B 1s2 2s2 2p6 3s2 3p3 C 1s2 2s2 2p6 3s2 3p6