Chemistry of Nitric Acid
Nitric acid is a strong acid with a pKa of −2: in aqueous solution, it completely ionizes into the nitrate ion NO3− and a hydrated proton, known as a hydronium ion, H3O+. Nitric Acid is a monoprotic acid because there is only one dissociation. The salts of nitric acid (which contain the nitrate ion) are also known as nitrates. The overwhelming majority of them are very soluble in water and in other polar liquid substances, such as ethanol.
At room temperature nitric acid gives off red or yellow fumes.
Nitric acid and its salts, the nitrates, should not be confused with nitrous acid and its salts, the nitrites.