NYJC_Prelim_CHEM_P1 ANS

1 NANYANG JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION Higher 1 CHEMISTRY 8872/01 Paper 1 Multiple Choice 25 September 2009 50 mins Additional Materials: Mult iple Choice Answer Sheet Data Booklet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, class and tutor’s name on the Answer Sheet in the spaces provided unless this has been done for you. 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 you 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 14 printed pages. [Turn over H1 Chemistry 8872/01 NYJC J2/09 Prelims

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 How many cations are present in 0.5 moles of sodium carbonate? A 0.5 B 1.0 C 3.01 x 10 23 D 6.02 x 1023 2 Ammonium nitrate can be produced by reaction between nitric acid and ammonia as shown below. If the yield of the reaction is 65 %, determine the volume of 5.0 mol dm –3 nitric acid required to r eact with ammonia (excess) to form 20 kg of ammonium nitrate. HNO3 + NH3  NH4NO3 A 32.5 dm3 B 50 dm3 C 77 dm3 D 385 dm3 3 When potassium chlorate(V), KClO 3, is heated at its melting point, it disproportionates to potassium chlorate(VII), KClO4, and potassium chloride. What is the maximum number of moles of potassium chlorate(VII) which can be produced from 0.1 mol potassium chlorate(V)? A 0.1 B 0.08 C 0.075 D 0.06 H1 Chemistry 8872/01 NYJC J2/09 Prelims

3 4 The use of the Data Booklet is relevant to thi s question. Which of the species contains 18 neutrons and 18 electrons? A 33P2– B 33S2– C 33P3– D 33S3– 5 Ga, Ge, As and Se are successive elements in Period 4. Which of the following statements is true? A Ga2+ and Ni are isoelectronic. B Both Se and Ge have two unpaired electrons at ground state. C First ionisation energy of Se is greater than that of As as the effective nuclear charge increases across the period. D As has only three unpaired electrons, thus the highest fluoride formed is AsF3. 6 A solution of ammonia in water contains A simple molecules only. B simple molecules and hydrogen bonded molecules only . C simple molecules, hydrogen bonded molecules and ions. D ions only. 7 Which one of the following pairs do the molecules hav e similar shapes? A AlCl3 and PCl3 B BF3 and NH3 C BeCl2 and H2O D AlCl3 and BCl3 H1 Chemistry 8872/01 NYJC J2/09 Prelims

4 8 The boiling point of 2,2-dimethylpropane is lower than that of