Ukrainian-born American chemist noted for preparing the first stable free radical triphenylmethyl (1900). His discovery met with initial skepticism since it was generally believed that long-lived radicals could not exist. Further findings convinced most chemists by 1911. Gomberg devoted the remainder of his career to pioneering researches in free-radical chemistry. He also discovered ethylene glycol, which is commonly used in antifreeze for automobile radiators. Gomberg was president of the American Chemical Society in 1931.