How can the following conversions be brought about :
Acetaldehyde to acetaldehyde phenyl hydrazone.

Explanation

To convert acetaldehyde to acetaldehyde phenylhydrazone, follow these steps:

### Step 1: Identify the Reactants
- The starting material is **acetaldehyde** (CH₃CHO).
- The reagent required for the conversion is **phenylhydrazine** (C₆H₅NH-NH₂).

### Step 2: Reaction Mechanism
- Acetaldehyde contains a carbonyl group (C=O) that can react with phenylhydrazine.
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