To calculate the formal charge on the nitrogen atom in the nitrate ion NO3 , we can use the following formula:Formal charge = Valence electrons of the atom - Non-bonding electrons - 1/2 Bonding electrons For nitrogen N in NO3:1. Valence electrons of nitrogen = 5 since nitrogen is in Group 15 2. Non-bonding electrons = 0 since all electrons are involved in bonding 3. Bonding electrons = 6 since there are three single bonds to the three oxygen atoms, and each bond has 2 electrons Now, we can plug these values into the formula:Formal charge = 5 - 0 - 1/2 6 Formal charge = 5 - 3Formal charge = +2However, we need to consider the resonance structures of the nitrate ion. In reality, the nitrate ion has three equivalent resonance structures, each with one double bond and two single bonds. So, we can distribute the +2 charge over the three N-O bonds:Formal charge on N averaged over resonance structures = +2 / 3 +0.67So, the formal charge on the nitrogen atom in the nitrate ion NO3 is approximately +0.67 when considering resonance structures.