Which of the following statements is true :

Options

A. Melting point of Phosphorous is less than that of Nitrogen
B. `N_(2)` is highly reactive while `P_(4)` is inert
C. Nitrogen shows higher tendency of catenation than P
D. N-N is weaker than P-P

Explanation

To determine which of the statements regarding nitrogen (N) and phosphorus (P) is true, we will analyze each statement step by step.

### Step 1: Analyze the first statement
**Statement:** The melting point of phosphorus is less than that of nitrogen.

- **Analysis:**
- Nitrogen (N2) has a weak N-N bond due to small size and electronic repulsions.
- Phosphorus (P4) has a larger atomic size, which allows it to handle electron repulsions better and form stronger bonds.
- Therefore, phosphorus has a higher melting point than nitrogen.

**Conclusion:** This statement is false.

### Step 2: Analyze the second statement
**Statement:** N2 is highly reactive than P4.

- **Analysis:**
- N2 has a triple bond, which makes it very stable and inert under normal conditions.
- P4, on the other hand, has single bonds and is more reactive compared to N2.

**Conclusion:** This statement is false.

### Step 3: Analyze the third statement
**Statement:** Nitrogen shows a higher tendency of catenation than phosphorus.

- **Analysis:**
- Catenation refers to the ability of an element to form chains or rings by bonding with itself.
- Nitrogen has a weak N-N bond, making it less capable of catenation.
- Phosphorus, with its stronger P-P bonds, can form more stable chains and rings.

**Conclusion:** This statement is false.

### Step 4: Analyze the fourth statement
**Statement:** N-N bond is weaker than P-P bond.

- **Analysis:**
- The N-N bond is indeed weaker due to the small size of nitrogen, which leads to significant electronic repulsions.
- The P-P bond is stronger because phosphorus can accommodate electron pairs better due to its larger size.

**Conclusion:** This statement is true.

### Final Answer
The true statement among the given options is: **N-N bond is weaker than P-P bond.**

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