Question

1. which of the following molecules has a trigonal pyramidal shape? a. methane (ch₄) b. ammonia (nh₃) c. water (h₂o) d. carbon dioxide (co₂)

Explanation:

In ammonia ($NH_3$), the central nitrogen atom has 3 bonding pairs with hydrogen atoms and 1 lone - pair. According to VSEPR (Valence - Shell Electron - Pair Repulsion) theory, the repulsion between the lone - pair and bonding pairs causes the molecule to adopt a trigonal pyramidal shape. Methane ($CH_4$) has a tetrahedral shape, water ($H_2O$) has a bent shape, and carbon dioxide ($CO_2$) has a linear shape.

Answer:

B. Ammonia ($NH_3$)