Cyanides

Cyanides, group of compounds containing the cyanide radical, CN (a carbon atom linked to a nitrogen atom). Organic cyanides, which occur in nature, as in some poisonous plants, are called nitriles. Though extremely poisonous, cyanides have great commercial importance in recovery of gold and silver from their ores, in case-hardening iron and steel, in fumigation and pest control, and in electroplating. The cyanides of potassium, sodium, barium, and calcium must be handled with extreme care because they liberate prussic acid (HCN), a weak acid that prevents the body cells from reacting with oxygen and quickly causes death.