Preparation of Aldehydes and Ketones
( i) By oxidation of alcohols Aldehydes and ketones are generally prepared by oxidation of primary and secondary alcohols, respectively.
( ii) By dehydrogenation of alcohols In this method, alcohol vapours are passed over heavy metal catalysts( Ag or Cu). Primary and secondary alcohols give aldehydes and ketones.
( iii) By ozonolysis of alkenes
( iv) By hydration of alkynes Acetylene on hydration gives acetaldehyde and other alkynes on hydration give ketones.