Assertion : Ammonia is a base .
Reason : It does not contaon `OH^(-)` ions .

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 .

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "Ammonia is a base."
- To evaluate this, we need to consider the definitions of bases according to different theories.

2. **Reviewing Base Definitions:**
- According to the **Arrhenius theory**, a base is a substance that produces hydroxide ions (OH⁻) when dissolved in water.
- According to the **Lewis theory**, a base is defined as an electron pair donor.

3. **Analyzing Ammonia (NH₃):**
- Ammonia (NH₃) does not contain hydroxide ions (OH⁻) in its molecular structure.
- However, ammonia can accept a proton (H⁺) to form ammonium (NH₄⁺) in solution, which indicates its basic nature.

4. **Applying the Theories:**
- Under the **Arrhenius definition**, ammonia does not qualify as a base because it does not produce OH⁻ ions directly.
- Under the **Lewis definition**, ammonia qualifies as a base because it has a lone pair of electrons on the nitrogen atom that can be donated.

5. **Evaluating the Reason:**
- The reason states, "It does not contain OH⁻ ions." While this is true, it does not correctly explain why ammonia is considered a base.
- The correct explanation should focus on ammonia's ability to donate an electron pair, which aligns with the Lewis definition.

6. **Conclusion:**
- Both the assertion and reason are true statements, but the reason provided does not correctly explain the assertion.
- Therefore, the correct answer is that the assertion is true, but the reason is not a valid explanation for the assertion.

**Final Answer:**
- Assertion: True
- Reason: True, but not the correct explanation of the assertion.

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