Chapter 10.1, Problem 10.4AFP

Interpretation Introduction

Interpretation:

Resonance forms of nitromethane, ${\text{H}}_3{\text{CNO}}_2$ with a formal charge on each resonance form is to be determined.

Concept introduction:

When bonds in a molecule can be expressed by different Lewis structures then resonance structures are used to depict the bonding in that molecule. These resonance structures have the same placement of atoms but different locations of bonding and lone pairs of electrons also one resonance form can be converted intoanother by moving lone pairs to bonding positions, and vice versa.

Formula to calculate the formal charge of the atom is as follows:

$\text{Formal}\text{charge}=\left(\begin{array}{l}\text{number}\text{of}\\ \text{valence}\\ \text{electrons}\end{array}\right)-\left(\left(\begin{array}{l}\text{number}\text{of}\\ \text{non-bonding}\\ \text{electrons}\end{array}\right)+\left(\frac{1}{2}\right)\left(\begin{array}{l}\text{number}\text{of}\\ \text{bonding}\\ \text{electrons}\end{array}\right)\right)$        (1)