Question

\[ \text{Why are }\alpha\text{-hydrogen atoms of aldehydes and ketones acidic in nature?} \]

Hint:

Aldehydes are generally more reactive than ketones towards nucleophilic addition. Clemmensen reduction converts carbonyl group into \(-CH_2-\) group.

Answer 1

Step 1: What is an alpha-hydrogen?
The $\alpha$-hydrogen is bonded to the carbon atom directly adjacent to the carbonyl ($C=O$) group.
Step 2: Reason for acidity.
When $\alpha$-H is removed as $H^+$, the resulting carbanion is stabilised by resonance with the carbonyl group, forming an enolate ion. This resonance delocalisation lowers the energy of the anion, making $H^+$ loss easier.
Step 3: Conclusion.
\[ \boxed{\alpha\text{-H atoms are acidic due to resonance stabilisation of the enolate anion formed after proton removal.}} \]