In the chemical NO3, the formal charge of nitrogen is + 1. When the charges of the one nitrogen atom and the three oxygen atoms are added together, the total charge of the nitrate ion is negative 1.
The formal charge is calculated by deducting the total number of valence electrons from the number of lone electrons and half of the bound electrons. No lone electrons, four bonding electrons, and five valence electrons make up the nitrogen atom. The charge is calculated using the equation 5 – 4 – 0 = 1. Two oxygen atoms in the ion have a formal charge of minus 1.
