Set 22 Chemistry [Paper] 2

1 SECTION A (60 Marks) Answer only three questions from this section . 1. Carbon, silicon, germanium, tin and lead are elements of group (IV) of the periodic table . a) (i).Write the outermost electronic configuration of group (IV) elements. (01 mark ) (ii).State the oxidation states of group (IV) elements. (01 mark) (iii).State how the stability of the oxidation states vary down the group (IV) elements. (02 marks) b) Describe the reactions of the elements with: i) Water. (06 marks) ii) Concentrated sulphuric acid. (06 marks) c) Write equations for the reactions between : i) Silicon (IV) oxide and hot concentrated hydrofluoric acid. (01½ marks) ii) Trileadtetraoxide and warm dilute nitric acid. (01½ marks) iii) Tin (II) chloride solution and iron (III) sulphate solution. (01½ marks) 2. a) Define the term relative atomic mass . (02 marks) b) Explain how relative atomic mass can be determined by the mass spectrometer . (09 marks) c) The mass spectrum of an element T contained four lines at mass/charge ration of 54, 56, 57 and 58. i) Explain what the term relative intensities mean and why the mass spectrum of element T contains 4 lines. (03 marks) ii) Calculate the relative atomic mass of element T . (02 marks) d) Explain why the values of relative atomic mass have no units.(01 mark) e) Thorium decays according to the following equation: 𝑇ℎ 90232 + 𝛂 X + 𝛃 Y + 𝛃 Z Determine the mass and atomic numbers of X, Y and Z. (03 marks) 3. (a).A gaseous alkene, Y diffuses 0.57735 times faster than nitrogen gas. Determine the molecular formula of alkene, Y. (03 mark s) b) On ozonolysis followed by hydrolysis alkene, Y produced propanal and propanone as the major organic products. Identify alkene, Y . (01 mark) c) Write the …