JEE Advanced · 2016 · 22 May 2016 · Paper 1 · Aldehydes Ketones and Carboxylic Acids

Tollen's test (silver mirror test) is positive for aldehydes and $\alpha$-hydroxy ketones. Option (A) is an $\alpha ,\beta$-unsaturated aldehyde (acrolein), which gives a positive test. Option (B) is benzaldehyde, an aromatic aldehyde, which gives a positive test. Option (C) is benzoin, an $\alpha$-hydroxy ketone, which can rearrange via enediol to an aldehyde and thus gives a positive test. Option (D) is chalcone, an $\alpha ,\beta$-unsaturated ketone with no $\alpha$-hydrogen on the carbonyl side, which does not give Tollen's test.