Question

which of the following molecules demonstrates a trigonal planar molecular shape?
bf₃
no₃
sf₃
h₃o⁺

Explanation:

Trigonal planar shape requires 3 bonding pairs and no lone pairs on the central atom (steric number 3). For BF₃: central B has 3 valence electrons, forms 3 bonds with F (no lone pairs), steric number 3 → trigonal planar. NO₃⁻ (note: likely typo, should be ion) also has trigonal planar shape, but SF₃⁺/⁻ (typo) and H₃O⁺ have lone pairs leading to different shapes. Among the options, BF₃ is a neutral molecule with trigonal planar shape.

Answer:

A. BF₃