Hydrolysis of an ester gives a carboxylic acid which on Kolbe's electrolysis yields ethane. The ester is `:`

Options

A. Ethyl methanoate
B. methyl ethanoate
C. Propylamine
D. Ethylamine

Answer

To solve the problem, we need to identify the ester that, upon hydrolysis, yields a carboxylic acid which can then undergo Kolbe's electrolysis to produce ethane (C2H6).

### Step-by-Step Solution:

1. **Understanding Hydrolysis of an Ester**:
- The hydrolysis of an ester involves the reaction with water (H2O) to produce a carboxylic acid and an alcohol. The general reaction can be represented as:
\[ RCOOR' + H2O \rightarrow RCOOH + R'OH \]
- Here, RCOOR' is the ester, RCOOH is the carboxylic acid, and R'OH is the alcohol.

2. **Identifying the Product from Kolbe's Electrolysis**:
- Kolbe's electrolysis involves the electrolysis of a carboxylic acid or its salt, leading to the formation of radicals. When the carboxylic acid undergoes Kolbe's electrolysis, it can lead to the formation of alkanes.
- The problem states that the product of Kolbe's electrolysis is ethane (C2H6). This means that the carboxylic acid formed from the ester must have two carbon atoms.

3. **Finding the Suitable Ester**:
- Since the carboxylic acid must have two carbon atoms, we can deduce that the ester we are looking for must be derived from acetic acid (CH3COOH).
- The simplest ester that can be formed from acetic acid is methyl acetate (methyl ethanoate), which has the structure:
\[ CH3COOCH3 \]

4. **Hydrolysis of Methyl Acetate**:
- When methyl acetate is hydrolyzed, it produces acetic acid and methanol:
\[ CH3COOCH3 + H2O \rightarrow CH3COOH + CH3OH \]

5. **Kolbe's Electrolysis of Acetic Acid**:
- Upon performing Kolbe's electrolysis on acetic acid (CH3COOH), the reaction leads to the formation of ethane (C2H6) through the decarboxylation process:
\[ 2 CH3COO^- \rightarrow C2H6 + 2 CO2 \]
- Here, two acetate ions (CH3COO^-) lose carbon dioxide (CO2) to form ethane.

6. **Conclusion**:
- Therefore, the ester that fits the criteria given in the question is **methyl acetate (methyl ethanoate)**.

### Final Answer:
The ester is **methyl acetate (methyl ethanoate)**.