NJC_2008 H2 CM Prelim P2

Registration Number ST group Name Do not open this booklet until you are told to do so. Write your name, class and registration number in the spaces provided at the top of this page. For Examiner’s Use 1 2 3 4 5 6 Total READ THESE INSTRUCTIONS FIRST Do not open this booklet until you are told to do so. Write your name, class and registration number in the spaces provided at the top of this page. A Y nswer ALL questions. ou are advised to show all the working in calculations. You may use a calculator. The number of marks is given in brackets [ ] at the end of each question or part of the question. This question paper consists of 14 printed pages (including this page) NATIONAL JUNIOR COLLEGE Preliminary Examinations 2008 CHEMISTRY Higher 2 9746/02 P A P E R 2 10 Sept 2008 1 hour 30 min Candidates are to answer on the Question paper. Additional Materials: Data Booklet 1

1 A section of the periodic table showing elements in periods 2 and 3 is shown below. T W X Y Element X has the following successive ionization energies. IE/ kJmol−1 1011 1907 2914 4963 6273 21267 25431 29872 (a) (i) Which group does element X belong to? [1] (ii) Do you expect the first ionization energy of element Y to be greater or smaller than that of X? Explain. [2] (b) (i) When dissolved in water, the chlorides of elements W and X produce solutions that turn blue litmus red. Explain. [2] 2

(ii) Deduce whether the same observation is seen for the chloride of element T. [2] (c) Element Z is in the same group as X but with a much greater proton number. The oxide of Z is seen to react with hydrochloric acid. Explain. [2] [Total: 9] 3

2 (a) (i) State two assumptions of the kinetic theory of gases. [2] (ii) Under what conditions is the behaviour of ammonia most nearly ideal? Explain your answer. [2] (b) The graph below shows experimental values of the product PV for a mass of ammonia against P at constant temperature. Which graph (A , B or C) shows the relationship between the product PV and P for carbon dioxide? Explain your choice. [2] 4

(c) Eth