Cyanide, SY uh nyd, is the name given to metal salts containing the CN group (a carbon atom linked to a nitrogen atom). Sodium cyanide (NaCN) and potassium cyanide (KCN) are important industrial chemicals. Both are used in the cyanide process of separating gold and silver from their ores, and in the hardening of steel. Both forms also are very poisonous if swallowed or absorbed through injured skin. Strong acids react with metal cyanides to make hydrogen cyanide (HCN), a deadly poison gas. Organic cyanides are nitriles. Acrylonitrile, important in the manufacture of fabrics, plastics, and synthetic rubber, is made from cyanide. Chemists use cyanide in solutions for electroplating and in the production of drugs and other chemicals. See also Gas chamber; Prussic acid.