Nitrogen does not form pentahalides as it does not have ............ .

Explanation

**Step-by-Step Solution:**

1. **Understanding Nitrogen's Electron Configuration**:
- Nitrogen has an atomic number of 7. Its electron configuration is 1s² 2s² 2p³. This indicates that nitrogen has two electrons in the first shell (1s) and five electrons in the second shell (2s and 2p).

2. **Identifying the Valency of Nitrogen**:
- The valency of an element is determined by the number of electrons it can lose, gain, or share to achieve a full outer shell. For nitrogen, with five valence electrons (2s² 2p³), it typically forms three bonds (valency of 3) by sharing three of its valence electrons.

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