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Q.
The compound of molecular formula $C_5H_{10}O(A)$ reacts with Tollen’s reagent to give silver mirror but does not undergo aldol condensation. The compound $A$ is
KEAMKEAM 2014Aldehydes Ketones and Carboxylic Acids
Solution:
Since, the compound reacts with Tollen's reagent so it must contain a $- CHO$ (aldehyde) group. Further, it does not give aldol condensation, it means that in it, $\alpha$ -hydrogen atom(s) is (are) absent. The structure of the given compound is as
Thus, $A$ is $2,2$ -dimethylpropanal (as it contains a $- CHO$ group but no $\alpha$ - $H$ atom).