Why does not formaldehyde take part in aldol condensation?

Explanation

### Step-by-Step Solution:

1. **Understanding Aldol Condensation**: Aldol condensation is a reaction that involves the combination of two aldehydes or ketones in the presence of a base or acid to form a β-hydroxy aldehyde or ketone, which can further dehydrate to yield an α,β-unsaturated carbonyl compound.

2. **Requirement of Alpha Hydrogen**: For aldol condensation to occur, the reactant must have at least one alpha hydrogen atom. Alpha hydrogens are the hydrogen atoms that are attached to the carbon atom adjacent to the carbonyl group (C=O).

3. **Analyzing Formaldehyde Structure**: The molecular formula of formaldehyde is HCHO. In this structure:
- The carbonyl carbon is the central carbon atom (C=O).
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