Ethylmercaptan is prepared by the reaction of the following, followed by hydrolysis :

Options

A. `C_2 H_5 MgBr + SO_2`
B. `C_2 H_5 Mg Br + S`
C. `C_2 H_5 MgBr + CS_2`
D. `C_2 H_5 Mg Br + H_2 S`.

Explanation

To prepare ethyl mercaptan (also known as ethane thiol), we can follow these steps:

### Step-by-Step Solution:

1. **Start with Ethyl Magnesium Bromide**:
- Ethyl magnesium bromide (C2H5MgBr) is a Grignard reagent. It is prepared by reacting ethyl bromide with magnesium in dry ether.

2. **Reaction with Sulfur**:
- Ethyl magnesium bromide reacts with sulfur (S) to form a thioether. The reaction can be represented as:
\[ C2H5MgBr + S \rightarrow C2H5-S-MgBr \]
- The product formed is an organosulfur compound where the ethyl group is bonded to sulfur.

3. **Hydrolysis**:
- The next step involves hydrolysis of the thioether. When the compound formed in the previous step is treated with water (H2O), it undergoes hydrolysis:
\[ C2H5-S-MgBr + H2O \rightarrow C2H5-SH + Mg(OH)Br \]
- The product of this hydrolysis is ethyl mercaptan (C2H5SH), which is also known as ethane thiol.

### Final Reaction Summary:
The overall reaction can be summarized as:
\[ C2H5MgBr + S \xrightarrow{\text{hydrolysis}} C2H5SH + Mg(OH)Br \]

### Conclusion:
Thus, ethyl mercaptan is prepared by the reaction of ethyl magnesium bromide with sulfur, followed by hydrolysis.

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