Which of the following amines gives carbylamine reaction?

Options

A. `C_(2)H_(2)NH_(2)`
B. `(C_(2)H_(5))_(2)NH`
C. `(C_(2)H_(5))_(3)N`
D. `CH_(3)NHC_(2)H_(5)`.

Answer

To determine which of the given amines gives a carbylamine reaction, we need to understand the nature of the amines and the conditions required for the carbylamine reaction to occur.

### Step-by-Step Solution:

1. **Understanding Carbylamine Reaction**: The carbylamine reaction is a chemical test used to detect primary amines. In this reaction, a primary amine reacts with chloroform (CHCl3) in the presence of a strong base (like NaOH or KOH) to form isocyanides. Secondary and tertiary amines do not give this reaction.

2. **Identifying the Amines**: We have the following amines to consider:
- A) C2H2NH2 (Ethylamine)
- B) C2H5NHNH (Hydrazine)
- C) C2H5 3N (Tertiary amine)
- D) CH3NH (Methylamine)

3. **Classifying the Amines**:
- **C2H2NH2**: This is a primary amine (NH2 group attached to a carbon chain).
- **C2H5NHNH**: This is a secondary amine (NH group attached to two carbon chains).
- **C2H5 3N**: This is a tertiary amine (N is attached to three carbon chains).
- **CH3NH**: This is also a primary amine.

4. **Analyzing Each Amine for Carbylamine Reaction**:
- **C2H2NH2**: As a primary amine, it will give a positive carbylamine reaction.
- **C2H5NHNH**: As a secondary amine, it will not give a carbylamine reaction.
- **C2H5 3N**: As a tertiary amine, it will not give a carbylamine reaction.
- **CH3NH**: As a primary amine, it will also give a positive carbylamine reaction.

5. **Conclusion**: The amines that give a carbylamine reaction are C2H2NH2 (option A) and CH3NH. However, since the question asks for which of the following amines gives the carbylamine reaction, the most straightforward answer is C2H2NH2 (option A).

### Final Answer:
The amine that gives the carbylamine reaction is **C2H2NH2** (Ethylamine).