Nitric acid is a strong oxidizing and corrosive inorganic acid, and its anhydride is nitrogen pentoxide. Nitric acid is less acidic than sulfuric acid and hydrochloric acid (PKa=- 1.3), easily soluble in water, completely ionized in water, its dilute solution is colorless and transparent at room temperature, and its concentrated solution is brown.
Nitric acid is unstable and easily decomposed by light. It should be stored in a brown bottle and kept away from light. Contact with reducing agent is strictly prohibited.
Nitric acid is mainly produced by ammonia oxidation in industry to produce fertilizers, explosives, nitrates and so on. In organic chemistry, the mixture of concentrated nitric acid and concentrated sulfuric acid is an important nitration reagent.
The concentration of industrial nitric acid is dilute nitric acid between 50% and 70%, and concentrated nitric acid between 96% and 98%.