The Lewis structure of nitric acid has a nitrogen atom at the center surrounded by three oxygen atoms, one of which joins to a hydrogen atom. The structure has one double bond between nitrogen and one of the hydrogen-free oxygen atoms.
The Lewis structure of nitric acid must account for 24 valance electrons. The two single bonds between nitrogen and oxygen account for four electrons. The double bond between nitrogen and oxygen account for another four and satisfy the octet rule for nitrogen. The bond between hydrogen and oxygen accounts for two electrons and fills hydrogen's outer shell. Four more electrons surround this oxygen nucleus, and the double-bonded oxygen requires four more electrons to fill its outer shell. The remaining oxygen nucleus requires the final six electrons to account for all 24.
Nitric acid is a strong acid that fully dissociates in water solutions. Aqueous solutions of nitric acid have a high H30+ ion concentration and a low pH. Placing a metal, such as zinc or magnesium, in the acid releases a large volume of flammable hydrogen gas. Adding copper or silver to the solution produces nitric oxide, which then reacts with oxygen in the atmosphere to produce nitrogen dioxide. It is a powerful oxidizer, which often reacts violently with organic materials.