ACJC H2 Chem 2012 Prelim P1 QP

© ACJC 2012 9647/01/Prelim/12 [Turn over 1 ANGLO-CHINESE JUNIOR COLLEGE DEPARTMENT OF CHEMISTRY Preliminary Examination CHEMISTRY 9647/01 Higher 2 Paper 1 Multiple Choice 12 September 2012 1 hour Additional Materials: Multiple Choice Answer Sh eet Data Booklet 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 18 printed pages. 9647/01/Prelim/012 ANGLO-CHINESE JUNIOR COLLEGE © ACJC 2012 Department of Chemistry [Turn over

© ACJC 2012 9647/01/Prelim/12 [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 The relative atomic mass of antimony, which consist s of the isotopes 121 Sb and 123 Sb, is 121.8. What is the percentage of 123 Sb in the isotopic mixture? A 40% B 45% C 50% D 55% 2 20 cm 3 of a gaseous unknown hydrocarbon was combusted in 100 cm 3 (an excess) of oxygen. After the combustion, the mixtur e was left to cool and the gaseous volume was 90 cm 3. Upon treatment with potassium hydroxide, the volume was decreased to 50 cm 3. What is the molecular formula of the unknown hydrocarbon? A CH 4 B C2H2 C C2H6 D C3H6 3 Species with unpaired electrons exhibit a property known as paramagnetism, that is, it is attracted by an external magnetic fi eld which is directly proportional to the number of unpaired electrons present in the species. Which of the following species is not paramagnetic? A Fe 3+ B Ti 2+ C Cu 2+ D Ca 2+

© ACJC 2012 9647/01/Prelim/12 [Turn over 3 4 The empirical formula of a fluorocarbon is CF 2. At the same temperature and pressure, 1 dm 3 of the fluorocarbon weighs 8.93 g while 1 dm 3 of fluorine gas weighs 1.80 g. What is the molecular formula of the fluorocarbon? A CF 2 B C2F4 C C4F8 D C5F10 5 Which of the following molecules will not form a hydrogen bond with another of its own molecules? A CH 3NH 2 B CH 3COCH 3 C CH 3CONH 2 D CH 3OH 6 Adrenaline is a hormone which, when secreted direct ly into the bloodstream, acts as a stimulant. The structure of adrenaline is given belo