How aldehydes and ketones are distinguished? Give two chemical reactions.

Explanation

The distinction between aldehydes and ketones can be done by following methods :
i) Fehling solution test: This test is given only by the aldehydes and not by ketones. Aldehydes give red precipitates of `Cu_2O` as given below:

ii) .Tollen.s reagent test (SIlver mirror test): Tollen.s reagent is the ammoniacal solution of silver nitrate, i.e., `[Ag(NH_3)_2]^(+) OH^(-)`. When aldehyde ts heated with this reagent, 1t gives metallic silver which shines like a mirror. Ketones donot give this reaction.
`underset("Aldehyde")(R - CHO) + underset("Tollen.s reagent") (2 [ Ag (NH_3)_2]^(+)) OH^(-) to underset("Acid")R - COOH + underset("Silver mirror")(2Ag + 4NH_3) + H_2O`