How can I calculate formal charge?
The formula for calculating the formal charge on an atom is simple.
Formal charge = [# of valence electrons] – [electrons in lone pairs + 1/2 the number of bonding electrons]
Since the number of bonding electrons divided by 2 is equal to the number of bonds surrounding the atom, this formula can be shortened to:
Formal Charge = [# of valence electrons on atom] – [non-bonded electrons + number of bonds].
Let's look at an example. Take the compound
Next, let's look at the hydrogen atoms in