Assertion: Carboxylic acids contain a carbonyl group but do not give characteristic reactions of the carbonyl group.
Reason: Due to resonance, the electrophilic nature of the carboxyl carbon is greatly reduced as compared to the carbonyl carbon in aldehydes and ketones.

Options

A. if both assertion and reson are true, and reason is the true explanation of the assertion.
B. If both assertion and reason are true, but reason is not the true explanation of the assertion.
C. if assertion is true, but reason is false.
D. If both assertion and reason are false.

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understanding the Assertion
The assertion states that "Carboxylic acids contain a carbonyl group but do not give characteristic reactions of the carbonyl group."

- Carboxylic acids indeed contain a carbonyl group (C=O) as part of their structure. However, they also contain a hydroxyl group (-OH).
- The presence of the hydroxyl group influences the reactivity of the carbonyl group. While aldehydes and ketones typically undergo nucleophilic addition reactions due to the electrophilic nature of their carbonyl carbon, carboxylic acids primarily participate in acid-base reactions and do not exhibit the same characteristic carbonyl reactions.

### Step 2: Understanding the Reason
The reason states that "Due to resonance, the electrophilic nature of the carboxyl carbon is greatly reduced as compared to the carbonyl carbon in aldehydes and ketones."

- In carboxylic acids, resonance occurs between the carbonyl group and the hydroxyl group. This resonance stabilizes the molecule and reduces the partial positive charge on the carbonyl carbon.
- In contrast, aldehydes and ketones do not have this additional -OH group, which means their carbonyl carbon is more electrophilic and can readily participate in nucleophilic addition reactions.

### Step 3: Conclusion
Both the assertion and the reason are true. The reason correctly explains why the assertion holds true. Therefore, the correct answer is that both the assertion and the reason are true, and the reason is a true explanation of the assertion.

### Final Answer:
Both the assertion and the reason are true, and the reason is a true explanation of the assertion.

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