The root of the ginger plant contains compounds with medicinal and flavouring properties. Three of the more important compounds are gingerol, shogaol and zingerone. (a) The structure of gingerol is shown. The CH₃O– group in gingerol is unreactive. [Figure: Structure of gingerol]

1. (a)Gingerol reacts with acidified potassium dichromate(VI). State the type of reaction and the functional group change which occurs during this reaction. type of reaction functional group change from to[1]
2. (b)(i)State the type of reaction needed to convert gingerol into shogaol.[1]
3. (b)(ii)State the reagents and conditions needed to convert gingerol into shogaol. reagents conditions[1]
4. (b)(iii)Shogaol reacts with hot, concentrated acidified manganate(VII) ions to form two organic products, Q and R. Draw the structures of Q and R. [Figure: Two empty boxes for structures of Q and R][2]
5. (c)Zingerone is formed from gingerol. Some reactions of zingerone are shown. Complete the table to identify the functional groups in zingerone. [Table with columns: 'reagent and conditions', 'observation', 'functional group in zingerone indicated by the observation' and rows for benzenediazonium chloride, 2,4-dinitrophenylhydrazine, Tollens' reagent][2]

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