Assertion: Ammonia acts as a ligand.
Reason : A lone pair of electrons on nitrogen can be donated to acceptor.

Options

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

Answer

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

### Step 1: Understand the Assertion
The assertion states that "Ammonia acts as a ligand."
- **Explanation**: A ligand is a species that can donate a pair of electrons to a central metal atom or ion to form a coordinate bond. Ammonia (NH₃) has a nitrogen atom that has a lone pair of electrons.

### Step 2: Understand the Reason
The reason states that "A lone pair of electrons on nitrogen can be donated to acceptor."
- **Explanation**: The nitrogen atom in ammonia has one lone pair of electrons. This lone pair can be donated to a metal ion (the acceptor), allowing ammonia to function as a Lewis base.

### Step 3: Evaluate the Truth of the Statements
- **Assertion**: True, because ammonia does indeed act as a ligand by donating its lone pair to a metal ion.
- **Reason**: True, because the lone pair on nitrogen is what allows ammonia to act as a ligand.

### Step 4: Determine the Relationship Between Assertion and Reason
- The reason provided explains why the assertion is true. The ability of ammonia to act as a ligand is directly due to the presence of the lone pair on nitrogen that can be donated.

### Conclusion
Since both the assertion and reason are true, and the reason correctly explains the assertion, the correct answer is:
**Both assertion and reason are true, and reason is the correct explanation for assertion.**

### Final Answer
**A**: Both assertion and reason are true, and reason is the correct explanation for assertion.

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