What type of aldehydes undergo Aldol condensation ?

Explanation

### Step-by-Step Solution:

1. **Understanding Aldol Condensation**: Aldol condensation is a reaction that involves the formation of a β-hydroxy aldehyde or ketone, followed by dehydration to yield an α,β-unsaturated carbonyl compound.

2. **Identifying Alpha Hydrogens**: For an aldehyde to undergo aldol condensation, it must have at least one alpha hydrogen. Alpha hydrogens are the hydrogen atoms attached to the carbon atom adjacent to the carbonyl group (C=O).

3. **Examples of Aldehydes with Alpha Hydrogens**:
- **Acetaldehyde (CH3CHO)**: This aldehyde has three alpha hydrogens on the methyl group (CH3). Therefore, it can undergo aldol condensation.
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