Question

which of the following complete lewis diagrams represents a molecule containing a bond angle that is closest to 120°?

Explanation:

Step1: Analyze molecule A

Molecule A is \( CO_2 \). The central atom \( C \) has \( 4 \) valence electrons. It forms two double bonds (\( C = O \)). The electron - pair geometry and molecular geometry of \( CO_2 \) are linear. The bond angle is \( 180^{\circ} \).

Step2: Analyze molecule B

Molecule B is \( CH_4 \). The central atom \( C \) has \( 4 \) valence electrons. It forms four single bonds (\( C - H \)). The electron - pair geometry and molecular geometry of \( CH_4 \) are tetrahedral. The bond angle is \( 109.5^{\circ} \).

Step3: Analyze molecule C

Molecule C is \( NH_3 \). The central atom \( N \) has \( 5 \) valence electrons. It forms three single bonds (\( N - H \)) and has one lone pair. The electron - pair geometry is tetrahedral, and the molecular geometry is trigonal pyramidal. The bond angle is approximately \( 107^{\circ} \) (due to the repulsion from the lone pair).

Step4: Analyze molecule D

Molecule D has a central \( C \) atom. One \( C \) forms three single bonds (two \( C - H \) and one \( C - C \)), and the other \( C \) forms a double bond (\( C = O \)). The central \( C \) (with three bonding pairs and no lone pairs) has a trigonal - planar electron - pair and molecular geometry. The bond angle around this \( C \) is \( 120^{\circ} \).

Answer:

D.