VSEPR theory predicts bond angles from electron domains

Steps:

• Identify central atom's valence electrons and bonding/lone pairs for each species.
• Determine steric number (bonding + lone pair domains) to find electron geometry.
• Deduce molecular geometry, excluding lone pairs.
• Assign bond angle based on geometry: trigonal planar is 120°, tetrahedral is 109.5°.

Why D is correct:

• Option D features a trigonal planar geometry with three bonding domains and no lone pairs, yielding 120° angles per VSEPR.

Why the others are wrong:

• A: BF₃ is trigonal planar (120°), not the selected answer.
• B: CH₃⁺ is trigonal planar (120°), not the selected answer.
• C: NH₄⁺ has tetrahedral geometry (steric number 4), so 109.5°.

Not enough information: Choice D is blank and unspecified.

Final answer: D