Aldehydes, ketones and carboxylic acids: reactions of ketones and aldehydes

Oxidation

• Aldehydes have a hydrogen atom attached to the carbonyl carbon atom which is readily lost during oxidation whereas ketones are much more resistant
• Tollen's reagent contains silver(I) ions which on reduction produce a silver mirror in the presence of aldehydes but not ketones
• Fehling's solution contains copper (II) ions which reduce to copper (I) (turning reddish-brown from blue) in the presence of aldehydes but not ketones
• Aldehydes oxidise to form an alkanoic acid

Reduction

• Both aldehydes and ketones can be reduced using lithium aluminium hydride in ether solution
• The aluminium hydride ion  provides a hydride ion (nucleophile) which attacks the partially positive carbon atom of the carbonyl group…