Assertion : Nitrogen is less reactive than molecular oxygen.
Reason: Bond length of `N_(2)` is shorter than that of oxygen.

Options

A. if both Assertion and Reason are true and reason is the correct explanation of the assertion.
B. if both assertion and reason are true but reason is not the correct expalanation of the assertion
C. if assertion is true, reason is false
D. both assertion and reason are false statements.

Explanation

To analyze the given assertion and reason, we will break down the steps systematically.

### Step 1: Understanding the Assertion
The assertion states that "Nitrogen is less reactive than molecular oxygen."
- **Explanation**: Reactivity is often determined by the strength of the bonds in the molecules. Nitrogen (N₂) has a triple bond, which is very strong, making it less likely to react. In contrast, molecular oxygen (O₂) has a double bond, which is weaker and allows it to react more readily with other substances.

### Step 2: Understanding the Reason
The reason provided is that "the bond length of N₂ is shorter than that of oxygen."
- **Explanation**: The bond length is inversely related to bond strength; shorter bonds are typically stronger. The bond length of nitrogen (N≡N) is shorter due to the presence of a triple bond, while the bond length of oxygen (O=O) is longer due to the double bond. This indicates that nitrogen's bond is stronger, contributing to its lower reactivity.

### Step 3: Comparing Reactivity
- **Comparison**: Since nitrogen has a triple bond (N≡N) and oxygen has a double bond (O=O), nitrogen is indeed less reactive than oxygen. The strength of the triple bond in nitrogen makes it less likely to participate in chemical reactions compared to the double bond in oxygen.

### Step 4: Evaluating the Reason
- **Evaluation**: The reason states that the bond length of N₂ is shorter than that of O₂. This is true because the triple bond in nitrogen is shorter than the double bond in oxygen. The shorter bond length corresponds to a stronger bond, which supports the assertion that nitrogen is less reactive than oxygen.

### Conclusion
Both the assertion and the reason are correct, and the reason provides a correct explanation for the assertion.

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