Chemistry

Question Analysis
This question involves VSEPR theory. The main focus is on identifying which molecule has a bond angle of 120°, which is characteristic of a Trigonal Planar geometry.

Key Concept Explanation
A trigonal planar geometry occurs when the central atom has three bonding pairs and no lone pairs, so the three electron domains arrange themselves 120° apart around a central atom to minimize repulsion equally.

Option Analysis
1. CH₄
Valence electrons: C: 4 valence electrons. H: 1 valence electron each.
Electron domains: Four bonding pairs and no lone pairs.
Result: tetrahedral → Bond angle: 109.5°.
2. NH₃
Valence electrons: N: 5 valence electrons. H: 1 valence electron each.
Electron domains: Three bonding pairs and one lone pair.
Result: trigonal pyramidal → Bond angle: ≈10...