Ethyl cyanide (A) can be converted to ethyl amine (B) by :

Options

A. `A overset(Sn//HCl) (to) B`
B. `A overset(H_(3) O^(+) ) (to)"" overset(NH_(3)// Delta)(to)"" overset(KBr O// Delta) (to) B`
C. `A overset(LiAlH_4) (to) B`
D. both (a), (c) are correct

Explanation

To convert ethyl cyanide (A) to ethyl amine (B), we can follow these steps:

### Step 1: Identify the Structures
- **Ethyl cyanide (A)** has the structure: CH3-CH2-C≡N (ethyl group attached to a cyano group).
- **Ethyl amine (B)** has the structure: CH3-CH2-NH2 (ethyl group attached to an amine group).

### Step 2: Choose the Reaction Pathway
To convert ethyl cyanide to ethyl amine, we can utilize a two-step reaction process:
1. **Hydrolysis of Ethyl Cyanide**: Treat ethyl cyanide with acidified water (H3O+). This will convert the cyano group (C≡N) into a carboxylic acid (C2H5COOH).
2. **Formation of Amide**: The carboxylic acid can then be reacted with ammonia (NH3) to form an amide (C2H5CONH2).
3. **Reduction of Amide to Amine**: Finally, treat the amide with KBr in the presence of a base to convert it into ethyl amine (C2H5NH2).

### Step 3: Write the Overall Reaction
The overall reaction can be summarized as follows:
1. **Hydrolysis**:
\[ CH3-CH2-C≡N + H3O^+ \rightarrow CH3-CH2-COOH \]
2. **Amidation**:
\[ CH3-CH2-COOH + NH3 \rightarrow CH3-CH2-CONH2 \]
3. **Reduction**:
\[ CH3-CH2-CONH2 + KBr \xrightarrow{\text{base, heat}} CH3-CH2-NH2 \]

### Conclusion
The correct method to convert ethyl cyanide (A) to ethyl amine (B) is through the pathway involving hydrolysis to form a carboxylic acid, followed by amidation and reduction. Thus, the correct answer is option B.

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