The number of non-bonding electrons of `N_(2)` is________.

Explanation

To determine the number of non-bonding electrons in the nitrogen molecule (N₂), we can follow these steps:

### Step 1: Identify the Atomic Number of Nitrogen
The atomic number of nitrogen (N) is 7. This means that a nitrogen atom has 7 electrons.

### Step 2: Determine the Electron Configuration
The electron configuration of nitrogen is:
- 1s² 2s² 2p³

### Step 3: Count the Valence Electrons
The valence electrons are the electrons in the outermost shell (the 2s and 2p orbitals):
- 2 electrons from the 2s orbital
- 3 electrons from the 2p orbital
Thus, the total number of valence electrons in a nitrogen atom is:
2 (from 2s) + 3 (from 2p) = 5 valence electrons.

### Step 4: Apply the Octet Rule
To achieve stability, nitrogen needs to complete its octet, which means it needs 8 electrons in its valence shell. Since nitrogen has 5 valence electrons, it needs 3 more electrons to complete its octet.

### Step 5: Forming the N₂ Molecule
In the N₂ molecule, two nitrogen atoms come together and share their valence electrons to form covalent bonds. Each nitrogen atom shares 3 of its valence electrons with the other nitrogen atom, resulting in:
- 3 covalent bonds between the two nitrogen atoms.

### Step 6: Calculate Non-Bonding Electrons
After forming 3 covalent bonds, each nitrogen atom effectively shares 3 electrons, which means:
- 3 (from one nitrogen) + 3 (from the other nitrogen) = 6 bonding electrons.
- Each nitrogen atom originally had 5 valence electrons, and since 3 are used for bonding, the remaining electrons are non-bonding.

Thus, the number of non-bonding electrons for each nitrogen atom is:
5 (total valence electrons) - 3 (bonding electrons) = 2 non-bonding electrons per nitrogen atom.

Since there are two nitrogen atoms in N₂:
- Total non-bonding electrons = 2 (from one nitrogen) + 2 (from the other nitrogen) = 4 non-bonding electrons.

### Final Answer
The number of non-bonding electrons in N₂ is **4**.

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