Give one reaction that can be used as a test for primary amines.

Explanation

### Step-by-Step Solution:

1. **Identify the Reaction**: The reaction that can be used as a test for primary amines is known as the **Carbylamine Reaction** or **Carbylamine Test**.

2. **Reagents Required**: The reagents used in this reaction are:
- A primary amine (RNH2)
- Chloroform (CHCl3)
- Alcoholic potassium hydroxide (KOH)
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