Reactions of aldehydes and ketonesAQA A-Level Chemistry: Mind map

Exam questions on Reactions of aldehydes and ketones

1. A technician has two unlabelled colourless liquids, one of which is propanal and the other propanone. She warms a sample of each separately with Tollens' reagent and with Fehling's solution in a hot water bath.
   State what is observed when propanone is tested with each reagent, and explain why propanal reacts differently.2 marks
2. A chemist reduces a sample of butanal and a sample of butanone separately, using NaBH₄ in aqueous solution at room temperature.
   Write an overall equation for the reduction of butanal, using [H] to represent the reductant, and name the type of mechanism.2 marks
3. Two isomeric carbonyl compounds, pentanal and pentan-2-one, are each treated with NaBH₄ in aqueous solution. The organic products are then separated and identified.
   Identify the organic product formed from each carbonyl compound, and state the class of alcohol in each case.3 marks