The English chemist and physicist Henry Cavendish discovered hydrogen by chemically reacting zinc with hydrochloric acid. Although hydrogen was previously studied and observed by other scientists, Cavendish received credit for identifying hydrogen as a unique chemical element.
Cavendish performed his experiment in 1766, when he first isolated hydrogen from the dissolution of zinc in hydrochloric acid. In his published works, Cavendish described the gas that was produced as "inflammable air from metals," concluding that any metal dissolved in any acid results in the formation of the same substance. He also noted that the gas produces water when ignited. Although Cavendish is generally recognized as having discovered the fundamental properties of hydrogen, it was the French chemist Antoine Lavoisier who gave the element its modern name.