Question

if the general formula of aldehyde and ketone is CnH2nO.then how can we differentiate between aldehyde and ketone

Answer 1

this general formula is formula for isomers...so u have some more information given to diffrentiate between them...

Answer 2

There are many tests that can be done to check the presence of group either it is aldehyde or ketone. Most common of them is Fehling solution test which is used to check the presence of aldehyde group. Tollen's test is also used which gives a silver mirror on the surface of test tube in which test is being conducted if an aldehyde group is present hence also known as silver mirror test.
Hope it will be helpful for you.
Good luck.