The nitrate ion NO3- is a polyatomic ion in which nitrogen is the central atom, surrounded by three oxygen atoms. Resonance structures are different ways to represent the same molecule or ion, where the atoms are in the same positions, but the electrons are distributed differently. In the case of the nitrate ion, there are three resonance structures. To identify them using formal charges and electron-dot structures also known as Lewis structures , follow these steps:1. Determine the total number of valence electrons: Nitrogen has 5 valence electrons, each oxygen has 6 valence electrons, and there is an extra electron due to the negative charge on the ion. So, the total number of valence electrons is 5 + 3 6 + 1 = 24.2. Draw the skeleton structure: Place the nitrogen atom in the center and surround it with the three oxygen atoms. Connect each oxygen atom to the nitrogen atom with a single bond. This uses 6 of the 24 valence electrons.3. Distribute the remaining valence electrons: There are 18 valence electrons left 24 - 6 . Place them as lone pairs on the oxygen atoms, giving each oxygen atom a total of 8 electrons including the bonding electron . This uses all 24 valence electrons.4. Calculate the formal charges: The formal charge of an atom in a molecule/ion is calculated as follows: Formal charge = Valence electrons of the atom - Non-bonding electrons + 1/2 Bonding electrons For nitrogen: Formal charge = 5 - 0 + 1/2 6 = 0 For each oxygen: Formal charge = 6 - 6 + 1/2 2 = -1 The sum of the formal charges is -3, but we need it to be -1 the charge of the nitrate ion . This indicates that we need to form double bonds to reduce the formal charges on the oxygen atoms.5. Create resonance structures: To create resonance structures, move one lone pair from an oxygen atom to form a double bond with the nitrogen atom. Do this for each oxygen atom, one at a time, resulting in three resonance structures. In each resonance structure, one oxygen atom has a double bond with nitrogen, while the other two oxygen atoms have single bonds.6. Calculate the formal charges for the resonance structures: For nitrogen: Formal charge = 5 - 0 + 1/2 8 = +1 For oxygen with a double bond: Formal charge = 6 - 4 + 1/2 4 = 0 For oxygen with a single bond: Formal charge = 6 - 6 + 1/2 2 = -1 The sum of the formal charges in each resonance structure is -1, which matches the charge of the nitrate ion.In conclusion, the nitrate ion NO3- has three resonance structures, each with one double bond between nitrogen and one of the oxygen atoms, and single bonds between nitrogen and the other two oxygen atoms. The formal charges in each resonance structure are +1 for nitrogen, 0 for the oxygen with a double bond, and -1 for the two oxygens with single bonds.