OCR A Jun 2016 Paper 4 Q2

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2 Some organic compounds contain nitrogen atoms. Examples include condensation polymers and azo dyes. (a) A section of a condensation polymer is shown below. CO(CH2)4CONH(CH 2)6NHCO(CH2)4CONH(CH 2)6NH (i) In the boxes below, draw the structures of the two monomers that form this condensation polymer. (ii) Name the type of condensation polymer and give a use for this polymer. TypeUse[1] [2]OCR 2016<br />
 (b) A student plans a two-step synthesis starting with phenylamine. The steps of the synthesis are shown below. NH2 HN CH3 HN CH3 step 1 step 2 phenylamine compound A NO2 compound B (i) In step 1, phenylamine reacts with ethanoic anhydride to make compound A and one other organic product. Draw the structure of ethanoic anhydride, with the functional group displayed, and suggest the structure of the other organic product formed in step 1. ethanoic anhydride other organic product [2] (ii) Calculate the mass of compound A that can be synthesised from 3.00 g of phenylamine in step 1. The percentage yield of this reaction is 61.0%. Mr (phenylamine) = 93.0 Give your answer to three significant figures.OCR 2016 mass of compound A =g [3] Turn over<br />
 The steps of the synthesis are shown again below. NH2 HN CH3 HN CH3 step 1 step 2 phenylamine compound A NO2 compound B (iii) In step 2, compound A is converted into compound B using a mixture of concentrated nitric acid and concentrated sulfuric acid. Outline, with the aid of curly arrows, the mechanism for the conversion of compound A into compound B. Use equations to explain how sulfuric acid acts as a catalyst in this reaction. [5]OCR 2016<br />
 (c) An azo dye is synthesised in two steps. In step 2 the diazonium ion is reacted with compound C to form the azo dye. Complete the flowchart for this synthesis. Write your answers in the boxes. H3C H3C NH2 step 1 Reagents Conditions N2 diazonium ion step 2 Conditions H3C Structure of compound C CH3 HO azo dyeOCR 2016 [4] [Total: 17] Turn over<br />

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