What is the approximate bond angle in the nitrate ion, NO_3^-?

• A. 109.5^ext{o}
• B. 90^ext{o}
• C. 120^ext{o}
• D. 180^ext{o}

Answer: (C)

Verified step by step guidance

1. Identify the central atom in the nitrate ion (NO_3^-), which is nitrogen (N).
2. Determine the number of regions of electron density around the central atom. In NO_3^-, nitrogen is bonded to three oxygen atoms and has no lone pairs, so there are three regions of electron density.
3. Use the VSEPR (Valence Shell Electron Pair Repulsion) theory to predict the molecular geometry. Three regions of electron density with no lone pairs correspond to a trigonal planar shape.
4. Recall that a trigonal planar molecular geometry has bond angles of approximately 120^\text{o}.
5. Conclude that the approximate bond angle in the nitrate ion is 120^\text{o}.