Hydrolysis of ethyl cyanide gives `:`

Options

A. Formic acid
B. Acetic acid
C. Propionic acid
D. Acetaldehyde

Explanation

To solve the question regarding the hydrolysis of ethyl cyanide, we will follow these steps:

### Step 1: Identify Ethyl Cyanide
Ethyl cyanide, also known as ethyl carbamate, has the chemical formula C2H5C≡N. It contains a cyano group (C≡N) attached to an ethyl group (C2H5).

### Step 2: Perform Acid Hydrolysis
When ethyl cyanide undergoes hydrolysis, it reacts with water in the presence of an acid (H+). The acid will protonate the cyano group, making it more susceptible to nucleophilic attack by water.

### Step 3: Formation of Intermediate
The first step of hydrolysis involves the attack of water on the cyano group:
- The H+ from the acid attacks the nitrogen of the cyano group.
- Water (H2O) donates a hydroxyl group (OH-) to the carbon of the cyano group.

This results in the formation of an intermediate compound, which is an amide:
\[ \text{C2H5C(OH)=N-H} \]

### Step 4: Further Hydrolysis
The intermediate can undergo further hydrolysis:
- Again, H+ from the acid will attack the nitrogen, and water will provide another hydroxyl group.
- This leads to the formation of a compound with two hydroxyl groups on the same carbon.

### Step 5: Elimination of Water
The presence of two hydroxyl groups on the same carbon is unstable, leading to the elimination of a water molecule. This results in the formation of an amide:
\[ \text{C2H5C(=O)NH2} \]

### Step 6: Final Hydrolysis to Carboxylic Acid
The amide can undergo further hydrolysis:
- H+ from the acid attacks the carbon of the carbonyl group (C=O).
- Water adds to the carbon, resulting in the formation of a carboxylic acid and ammonia.

The final product is propionic acid (C2H5COOH) and ammonia (NH3).

### Conclusion
The hydrolysis of ethyl cyanide results in the formation of propionic acid.

### Final Answer
The correct answer is **C: Propionic acid**.

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