Which of the following is effective for the hydrolysis of an ester ?

Options

A. Dilute alkali
B. Dilute acid
C. Water
D. `CH_(3) OH`

Answer

To determine which of the following is effective for the hydrolysis of an ester, we need to understand the process of ester hydrolysis. Hydrolysis of an ester involves the reaction of the ester with water, often in the presence of an acid or a base, to produce an alcohol and a carboxylic acid.

### Step-by-Step Solution:

1. **Identify the Ester**:
- An ester has the general formula RCOOR', where R and R' are hydrocarbon chains or groups.

2. **Understand Hydrolysis**:
- Hydrolysis is the reaction of an ester with water (H2O) to form an alcohol (R'OH) and a carboxylic acid (RCOOH).

3. **Choose the Hydrolysis Method**:
- Hydrolysis can occur under acidic or basic conditions:
- **Acidic Hydrolysis**: Involves the addition of an acid (like HCl or H2SO4) which protonates the ester, making it more electrophilic and susceptible to nucleophilic attack by water.
- **Basic Hydrolysis (Saponification)**: Involves the addition of a base (like NaOH or KOH) which reacts with the ester to form a carboxylate ion and an alcohol.

4. **Mechanism of Hydrolysis**:
- In basic hydrolysis, the hydroxide ion (OH-) acts as a nucleophile and attacks the carbonyl carbon of the ester, leading to the formation of a tetrahedral intermediate. This intermediate then collapses to yield the carboxylate ion and the alcohol.

5. **Conclusion**:
- The most effective method for hydrolysis of an ester is typically in the presence of a dilute base (like NaOH) or dilute acid (like HCl), as these conditions facilitate the reaction and yield the desired products efficiently.

### Final Answer:
The effective method for the hydrolysis of an ester is the use of a dilute base (like NaOH) or dilute acid (like HCl).

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