Differnce between nitrate,nitrite, nitride
Nitrate NO3-s the anion of conjugate base of nitric acid. The nitrate anion carries a formal charge of -1. This results from a combination formal charge in which each of the three oxygen atoms carries a −2⁄3 charge, whereas the nitrogen carries a 1+ charge, all these adding up to formal charge of the polyatomic nitrate ion.
In case of nitrite ion NO2-, there are 2 negative charges of two oxygen atoms, and one positive charge of the central nitrogen atoms. Hence the total charge on the whole molecule is (-2+1=-1).
A nitride N3- is a compound of nitrogen in which nitrogen has a formal oxidation state of −3.