CJC Prelim_P1

1 CANDIDATE NAME CLASS 2T CHEMISTRY 9729/01 Paper 1 Multiple Choice Wednesday 29 August 2018 1 hour Additional Materials: Mult iple 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 NRIC/FIN number on the Answer Sheet in the spaces provided. 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 16 printed pages. Catholic Junior College JC 2 Preliminary Examinations Higher 2

2 9729/01/CJC JC2 Preliminary Examination 2018 1 A sample of tungsten contains four naturally occurring isotopes, 182W, 183W, 184W and 186W. The relative atomic mass of tungsten in this sample is 183.9. What is the percentage of the isotope 182W in this sample? Isotope Relative Abundance (%) 182W ? 183W ? 184W 30.6 186W 28.6 A 10.5 C 26.4 B 14.4 D 40.8 2 20 cm 3 of 0.100 mol dm −3 of potassium ferrate( VI), K 2FeO4, reacts with sodium ethanedioate, Na2C2O4, in an acidic medium to produce 144 cm 3 of carbon dioxide gas at room temperature and pressure. The half equation of C2O42– is shown as follows: 2CO2 + 2e– C 2O42– What is the final oxidation state of the iron-containing species after the reaction? A +1 B +2 C +3 D +4 3 When attracted by a strong magnet, some species are able to exhibit paramagnetism. Such species contain unpaired electrons which are able to spin in a way which aligns parallel to the magnetic field. Which of the following species in the ground state is able to exhibit paramagnetism? 1 O 2 A l+ 3 Ti2+ 4 Cu+ A 1 and 3 only B 2 and 4 only C 1, 3 and 4 only D 2, 3 and 4 only

3 9729/01/CJC JC2 Preliminary Examination 2018 [Turn over 4 Phosphorus(V) chloride, PCl5 dissolves in a suitable polar solvent to produce two ions, [PCl4]+ and [PCl6]–. Which of the following shows the correct shape for PCl5, [PCl4]+ and [PCl6]–? PCl5 [PC l4]+ [PC l6]– A trigonal planar square planar square pyramidal B trigonal bipyramidal square planar octahedral C trigonal planar distorted tetrahedral square pyramidal D trigonal bipyramidal tetrahedral octahedral 5 The table shows the boiling point of some halogenoalkanes. compound boiling point/ °C CH3CH2Cl 12.3 CH3CH2Br 34.8 CH3CH2I 70.0 Which of the following correctly explains the difference in the boiling point? 1 the electronegativity di