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 determine which bond of the carboxylic acid undergoes cleavage during the esterification process with an alcohol, we can break down the reaction step-by-step.

### 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:
\[ \text{RCOOH (carboxylic acid) + R'OH (alcohol) } \rightarrow \text{ RCOOR' (ester) + H2O} \]

2. **Identifying Bonds in Carboxylic Acid**: The structure of a carboxylic acid (RCOOH) contains:
- A carbonyl group (C=O)
- A hydroxyl group (C-OH)

3. **Mechanism of Esterification**: During the esterification reaction:
- The hydroxyl group (C-OH) of the carboxylic acid interacts with the alcohol.
- The alcohol's hydroxyl group (R'-OH) donates a proton (H+) to the carbonyl oxygen, making the carbonyl carbon more electrophilic.

4. **Cleavage of Bonds**: In the reaction mechanism:
- The bond between the carbon of the carboxylic acid and the hydroxyl group (C-OH) undergoes cleavage.
- This results in the formation of the ester (RCOOR') and the release of water (H2O).

5. **Conclusion**: Therefore, the bond that breaks during the esterification of a carboxylic acid with an alcohol is the C-O bond of the hydroxyl group (C-OH) in the carboxylic acid.

### Final Answer:
The bond that undergoes cleavage during the esterification of carboxylic acid with alcohol is the C-O bond of the hydroxyl group (C-OH).