Set 4 Chemistry [Paper] 1

Think Like An Economist Quote B y Tr.Js Felix B ig Acholiboy Rubangakene 1 SECTION A-46 MARKS Attempt all questions in this section. 1. Complete the following equations and outline the mechanism for each of the reactions. a. (CH3)3CBr ............................................ (02½ mark)OH- (aq) Heat ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………… ………………………………… …………………………….. b.OH + CH3COCl .............................. (03 marks)NaOH(aq) Heat ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ……………………………………………………………………………………………… ………… ………………………………………………………………………………………………………… …………………………………………………………………………… …………………………….. 2. Thorium decays according to the following equation. 𝑇ℎ90232 + α X + β Y + β Z a) Identify the following species . (03 marks) X: …………………………………………………………………………………………………. Y: …………………………………………………………………………………………………. Z: …………………………………………………………………………………………………. Think Like An Economist Quote B y Tr.Js Felix B ig Acholiboy Rubangakene 2 b) The half -life of Thorium -232 is 234 days . Determine the t ime taken for Thorium to decay by 12.5% of its original value . (03 marks) …………………………………………………………………………………………………… …………………………………………………………………………………………………… ……………………………………………………… …………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… ……… …………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………… ……………………………………………………………………… 3. Write equations for the reaction between water and: (@01½ marks) a) Sodium hydride. …………………………………………………………………………………………………… …………………………………………………………………………………………………… b) Phosphorus (V) oxide. …………………………………………………………………………………………………… …………………………………………………………………………………………………… c) Beryllium ca rbide. …………………………………………………………………………………………………… …………………………………………………………………………… ……………………… 4. 50.0cm3 of a vaporized alcohol G, CnH2n+2OH diffused through a porous plug in 19.85 seconds . Under the same conditions, the same volume of hydrogen gas diffused through under the same conditions in 21.85 seconds . a) (i). Calculate the molecular mass of G. (02 marks) ………………………………………………………………………………………………… ………………………………………………………………………………………………… ………………………………………………………………………………………………… ………………………………………………………………………………………………… Think Like An Economist Quote B y Tr.Js Felix B ig Acholiboy Rubangakene 3 ………………………………………………………………………………………………… ……………………………………………………… ………………………………………… ………………………………………………………………………………………………… ………………………… ……………………………………………………………………… ………………………………………………………………………………………………… ………………………………………………………………………………………………… ………………………………………………………………………………………………… (ii).Determine the molecular formula of G. (01 mark) …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… ………………………………………………………………………………… ………………… …………………………………………………………………………………………………… ……… …………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… b) (i).Write the structural formulae and the IUPAC names of all the possible isomers of G. (02 marks) …………………………………………………………………………………………………… ……… …