Assertion (A): An aqueous solution of ammonium acetate acts as a buffer solution.
Reason (R) : A buffer solution reacts with small quantities of hydrogen or hydroxy ions and keps the `pH` almost same.

Options

A. If both (A) and (R) are correc, and (R) is the correct explanation of (A).
B. If both (A) and (R) are correct but (R) is not the correct explanation of (A).
C. If (A) is correct, but (R) is incorrect.
D. If (A) is incorrect, but (R) is correct.

Explanation

To solve the question regarding the assertion and reason provided, we will analyze both statements step by step.

### Step 1: Analyze the Assertion (A)
**Assertion (A)**: An aqueous solution of ammonium acetate acts as a buffer solution.

- **Explanation**: Ammonium acetate (NH4CH3COO) is a salt derived from a weak acid (acetic acid, CH3COOH) and a weak base (ammonia, NH3). When dissolved in water, it dissociates into ammonium ions (NH4+) and acetate ions (CH3COO-). This combination allows the solution to resist changes in pH upon the addition of small amounts of acids or bases, thus functioning as a buffer solution.

### Step 2: Analyze the Reason (R)
**Reason (R)**: A buffer solution reacts with small quantities of hydrogen or hydroxyl ions and keeps the pH almost the same.

- **Explanation**: This statement is true. Buffer solutions are designed to maintain a relatively constant pH when small amounts of acids (which provide H+ ions) or bases (which provide OH- ions) are added. The buffer components (in this case, NH4+ and CH3COO-) can react with these ions to minimize changes in pH.

### Step 3: Determine the Relationship Between A and R
- Both statements A and R are correct.
- However, while R correctly describes the function of a buffer solution, it does not specifically explain why ammonium acetate acts as a buffer. The reason does not provide insight into the specific components of ammonium acetate that contribute to its buffering capacity.

### Conclusion
The correct answer is that both A and R are correct, but R is not the correct explanation of A.

### Final Answer
**Option 3**: A is correct but R is incorrect.

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