Which of the following statement is not correct about dinitrogen.

Options

A. `N_(2)` is a diatomic molecule.
B. Hydrogen bonding is absent in `NH_(3)`
C. Nitrogen shows covalency of 3.
D. Nitrogen is chemically inert.

Explanation

To determine which statement about dinitrogen (N2) is not correct, we need to analyze the provided options step by step.

### Step 1: Identify the properties of dinitrogen (N2)
Dinitrogen, represented as N2, is a diatomic molecule consisting of two nitrogen atoms. It is known for its strong triple bond, which makes it chemically inert under standard conditions.

### Step 2: Evaluate the statements
1. **N2 is a diatomic molecule.**
- This statement is correct. Dinitrogen consists of two nitrogen atoms.

2. **Hydrogen bonding is absent in NH3.**
- This statement is incorrect. Ammonia (NH3) does exhibit hydrogen bonding due to the presence of nitrogen, which is highly electronegative, allowing it to form hydrogen bonds with other molecules.

3. **Nitrogen has a covalency of 3.**
- This statement is correct. Nitrogen typically forms three covalent bonds in compounds, as seen in ammonia (NH3) and other nitrogen-containing compounds.

4. **Nitrogen is chemically inert.**
- This statement is also correct. The strong triple bond in N2 makes it relatively inert and unreactive under normal conditions.

### Step 3: Identify the incorrect statement
From the evaluation, the statement that is not correct is: **"Hydrogen bonding is absent in NH3."** This is the only incorrect statement regarding dinitrogen and its properties.

### Final Answer
The statement that is not correct about dinitrogen is: **"Hydrogen bonding is absent in NH3."**

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