A : In esterification reaction , HCOOH is the most reactive acid among carboxylic acid .
R : Alcohol acts as nucleophile

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false , then mark (3)
D. If both Assertion and Reason are false statements , then mark (4)

Answer

To solve the assertion and reason question regarding the reactivity of methanoic acid (HCOOH) in esterification reactions, we will analyze both the assertion (A) and the reason (R) step by step.

### Step 1: Analyze the Assertion (A)
The assertion states: "In esterification reaction, HCOOH is the most reactive acid among carboxylic acids."

- **Explanation**: Esterification is a reaction between a carboxylic acid and an alcohol to form an ester and water. The reactivity of carboxylic acids in this reaction is influenced by the structure of the acid. Methanoic acid (HCOOH), being the simplest carboxylic acid, has no alkyl groups that can donate electron density through the inductive effect. This results in a higher positive charge on the carbonyl carbon, making it more susceptible to nucleophilic attack by the alcohol.

### Step 2: Analyze the Reason (R)
The reason states: "Alcohol acts as a nucleophile."

- **Explanation**: In the esterification reaction, the alcohol indeed acts as a nucleophile. The oxygen atom in the alcohol has lone pairs of electrons, which it can use to attack the electrophilic carbon of the carboxylic acid. This nucleophilic attack is essential for the formation of the ester.

### Step 3: Determine the Truth Value of A and R
- **Truth Value of A**: True. Methanoic acid is indeed the most reactive carboxylic acid in esterification reactions.
- **Truth Value of R**: True. Alcohol acts as a nucleophile in the esterification reaction.

### Step 4: Check if R is the Correct Explanation for A
- While both statements are true, the reason (R) does not explain why methanoic acid is the most reactive carboxylic acid. The reason focuses on the role of alcohol as a nucleophile, but it does not address the structural aspects of methanoic acid that contribute to its reactivity.

### Conclusion
- **Final Answer**: Both A and R are true, but R is not the correct explanation for A. Therefore, the correct option would be that both statements are true, but the reason is not the correct explanation for the assertion.

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