Why `NF_(3)`, is pyramidal while `BF_(3)` is triangular planar, though both are tetra atomic molecules?

Explanation

To understand why NF₃ is pyramidal while BF₃ is trigonal planar, we need to analyze the molecular geometry of both compounds based on their hybridization and the presence of lone pairs.

### Step-by-Step Solution:

1. **Identify the Central Atom and Count Valence Electrons:**
- For NF₃ (Nitrogen trifluoride), the central atom is Nitrogen (N), which belongs to Group 15 of the periodic table. Nitrogen has 5 valence electrons.
- For BF₃ (Boron trifluoride), the central atom is Boron (B), which belongs to Group 13. Boron has 3 valence electrons.

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