1. Draw the Lewis Structure
* Nitrogen (N) is the central atom, and it has 5 valence electrons.
* Oxygen (O) has 6 valence electrons each.
The Lewis structure looks like this:
O
||
N - O
2. Count the Electron Domains
An electron domain is a region of space around an atom where electrons are concentrated. It can be a single bond, a double bond, a triple bond, or a lone pair of electrons.
* In NO2, there are three electron domains around the central nitrogen atom:
* One double bond to the left oxygen atom.
* One double bond to the right oxygen atom.
* One lone pair of electrons on the nitrogen atom.
3. Determine the Electron Domain Geometry
Based on the three electron domains, the electron domain geometry is trigonal planar. This means that the electron domains are arranged in a triangular shape around the nitrogen atom.
Important Note: While the electron domain geometry is trigonal planar, the *molecular* geometry of NO2 is bent due to the presence of the lone pair on the nitrogen atom. Lone pairs exert a greater repulsive force on the bonding pairs, causing the molecule to bend.
