During esterification of carboxylic acid with alcohol which bond of carboxylic acid undergoes cleavage?

Options

A. C - C
B. C = O
C. C - O
D. O - H

Answer

To answer the question regarding which bond of carboxylic acid undergoes cleavage during the esterification process with alcohol, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Esterification**:
- Esterification is a chemical reaction between a carboxylic acid and an alcohol, resulting in the formation of an ester and water. The general reaction can be represented as:
\[ RCOOH + R'OH \rightarrow RCOOR' + H_2O \]
- Here, \( RCOOH \) is the carboxylic acid, \( R'OH \) is the alcohol, and \( RCOOR' \) is the ester formed.

2. **Identifying the Bonds in Carboxylic Acid**:
- A carboxylic acid has the following structure:
\[ R-C(=O)-OH \]
- In this structure, the bonds present are:
- C-C (single bond between R and C)
- C=O (double bond between C and O)
- C-O (single bond between C and O in the hydroxyl group)
- O-H (single bond between O and H in the hydroxyl group)

3. **Analyzing the Reaction Mechanism**:
- During the esterification reaction, the hydroxyl group (–OH) of the carboxylic acid is removed. This leads to the cleavage of the C-O bond in the carboxylic acid.
- The hydrogen from the hydroxyl group of the alcohol also combines with the hydroxyl group of the carboxylic acid to form water.

4. **Conclusion on Cleavage**:
- The bond that undergoes cleavage in the carboxylic acid during esterification is the C-O bond (the bond between the carbon of the carboxylic acid and the oxygen of the hydroxyl group).
- Therefore, the correct answer to the question is that the **C-O bond** of the carboxylic acid undergoes cleavage.

### Final Answer:
The bond that undergoes cleavage in carboxylic acid during esterification is the **C-O bond**.

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