International Union of Pure and Applied Chemistry
International Union of Pure and Applied Chemistry (IUPAC), an international organization est. 1919 to advance the chemical sciences and contribute to the application of chemistry to the service of humanity. IUPAC is an association of national chemistry associations that is reponsible for the standardization of weights, measures, symbols, and terminology. It also publishes definitive atomic and chemical data and establishes standard methods for use in various laboratories.