Nitric acid Nitric acid can oxidize non-active metals such as copper and silver. With these non-active or less electropositive metals the products depend on temperature and the acid concentration. For example, copper reacts with dilute nitric acid at ambient temperatures with a 3:8 stoichiometry: The nitric oxide produced may react with atmospheric oxygen to give nitrogen dioxide. With more concentrated nitric acid, nitrogen dioxide is produced directly in a reaction with 1:4 stoichiometry: Upon reaction with nitric acid, most metals give the corresponding nitrates. Some metalloids and metals give the oxides; for instance, Sn, As, Sb, and Ti are oxidized into SnO,
Acid–base reaction HA represents the acid, B represents the base, BH represents the conjugate acid of B, and A represents the conjugate base of HA. For example, a Brønsted-Lowry model for the dissociation of hydrochloric acid (HCl) in aqueous solution would be the following: The removal of H from the HCl produces the chloride ion, Cl, the conjugate base of the acid. The addition of H to the HO (acting as a base) forms the hydronium ion, HO, the conjugate acid of the base. Water is amphoteric—that is, it can act as both an acid and a base. The Brønsted-Lowry model explains