Aldehydes are readily oxidised to carboxylic acids but ketones are not readily oxidised.
Aldehydes -------> Carboxylic Acid
Reagent: Potassium Dichromate
Condition: Warm and under reflux
Equation: RCHO + [O] ------> RCOOH
i.e. CH3CHO +[O] ---> CH3COOH
Observation: orange solution turns green.
(note: when synthesising an aldehyde in a lab through oxidation of a primary alcohol the aldehyde is quickly removed in order to avoid further oxidation which would result in the formation of a carboxylic acid).
Ketones CAN'T be oxidised…