JJC_H2 Chemistry 9746 Prelim P1 Question Paper _ Answers

Answers to 2008 J2 Chemistry Preliminary Exams Paper 1 1. D 11. A 21. A 31. C 2. C 12. B 22. A 32. C 3. C 13. B 23. A 33. A 4. C 14. A 24. B 34. B 5. B 15. A 25. D 35. D 6. D 16. C 26. B 36. B 7. A 17. C 27. B 37. B 8. D 18. D 28. C 38. A 9. A 19. D 29. D 39. B 10. C 20. D 30. B 40. B

JURONG JUNIOR COLLEGE PRELIMINARY EXAMINATION 2008 H2 CHEMISTRY PAPER 1 9746 / 1 Wednesday 27 th August 2008 1 hour INSTRUCTIONS TO CANDIDATES: Do not open this question booklet until you are told to do so. Write your name and class on the answer sheet in the spaces provided. There are 40 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. INFORMATION FOR CANDIDATES: 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. A Data Booklet is provided. _____________________________________________________________________ This question booklet consists of 16 printed pages, including this page. [Turn over Page 2 of 16

SECTION A (30 MARKS) For each question there are four possible answers, A, B, C and D. Choose the one you consider to be correct. 1. Potassium iodate(V) can be used as a st andard in iodine-thiosulfate titrimetry since it reacts with iodide ions according to the equation: IO3 −(aq) + 5I−(aq) + 6H+(aq) → 3I2(aq) + 3H2O(l) How many moles of s odium thiosulfate, Na 2S2O3, is needed to react with the iodine produced by 1 mole of iodate(V) ions? A 3 B 4 C 5 D 6 2. The successive ionisation energies of two elements, M and N, are given. Ionisation energy / kJ mol −1 1st 2 nd 3 rd 4 th 5 th 6 th 7 th 8th M 1090 2350 4610 6220 37800 47000 - - N 1251 2298 3822 5158 6542 9362 11018 33604 What is the formula of the compound that M and N are likely to form? A MN B M 2N2 C MN 4 D M 4N 3. Ions of two isotopes of the transition metal nickel are shown below. Ni 2+ 60 Ni2+ 58 28 28 Which one of the following statements is correct? A The Ni2+ ion has more protons than the 58 28 Ni2+ ion. 60 28 B The electronic configuration of both Ni2+ ions is 1s2 2s2 2p6 3s2 3p6 3d6 4s2. C These Ni2+ ions have the same number of el ectrons but a different number of neutrons. D The Ni2+ ion will be deflected more than the Ni2+ ion under the same magnetic field. 60 28 58 28 4. A certain mass of an ideal gas occupies a volume of 1 dm 3 at 20 oC. If the pressure remains unchanged, at what temperature will its volume be 2 dm3? A 40 oC B 293 oC C 313 oC D 586 oC Page 3 of 16

5. Which one of the following, in the solid st