The nitrate ion NO3- has three possible resonance structures. These structures are formed by the delocalization of the electrons in the molecule, which means that the electrons are shared among the different oxygen atoms. The three resonance structures are as follows:1. In the first resonance structure, the nitrogen atom is double-bonded to one of the oxygen atoms and single-bonded to the other two oxygen atoms. Each of the single-bonded oxygen atoms carries a negative charge.2. In the second resonance structure, the nitrogen atom is double-bonded to a different oxygen atom, while the other two oxygen atoms are single-bonded. The single-bonded oxygen atoms carry a negative charge.3. In the third resonance structure, the nitrogen atom is double-bonded to the third oxygen atom, and the other two oxygen atoms are single-bonded. The single-bonded oxygen atoms carry a negative charge.These three resonance structures contribute to the overall structure and properties of the nitrate ion in the following ways:1. Delocalization of electrons: The electrons are delocalized among the three oxygen atoms, which means that they are shared equally among them. This delocalization leads to a more stable molecule.2. Bond length: Due to the delocalization of electrons, the bond lengths between the nitrogen and oxygen atoms are equal and intermediate between a single bond and a double bond. This equal bond length contributes to the overall stability of the molecule.3. Charge distribution: The negative charge is distributed equally among the three oxygen atoms, which also contributes to the stability of the nitrate ion.4. Reactivity: The resonance structures of the nitrate ion make it a good electrophile, meaning it can easily accept electrons from other molecules. This property makes the nitrate ion highly reactive and an important component in various chemical reactions, such as those involving nitrogen-containing compounds.