Question

1. this is a diagram of ammonia. this molecule has a central nitrogen atom singly bonded to three hydrogen atoms. the nitrogen atom also has one lone pair of electrons. the shape of this molecule can be classified as _______. a) linear b) trigonal planar c) tetrahedral d) trigonal pyramidal

Explanation:

To determine the molecular shape of ammonia (\(NH_3\)):

1. The central nitrogen atom has 3 bonding pairs (with H atoms) and 1 lone pair of electrons.
2. The electron - pair geometry (considering both bonding and lone pairs) is tetrahedral (4 regions of electron density: 3 bonds + 1 lone pair).
3. However, the molecular shape (considering only the positions of the atoms) is determined by the arrangement of the bonding pairs around the central atom, accounting for the lone pair's repulsion. A central atom with 3 bonding pairs and 1 lone pair has a trigonal pyramidal shape.

• Linear (A) has 2 bonding regions.
• Trigonal planar (B) has 3 bonding regions with no lone pairs.
• Tetrahedral (C) would be the case with 4 bonding regions (no lone pairs), like in \(CH_4\).

Answer:

D) trigonal pyramidal