Photo from the Nobel Foundation archive.
Svante August Arrhenius
Born: 19 February 1859, Vik, Sweden
Died: 2 October 1927, Stockholm, Sweden
Affiliation at the time of the award: Stockholm University, Stockholm, Sweden
Prize motivation: "in recognition of the extraordinary services he has rendered to the advancement of chemistry by his electrolytic theory of dissociation."
Prize share: 1/1
A connection between chemical and electrical phenomena became apparent in the 19th century, but it was unclear just what this relationship was. Svante Arrhenius studied how electrical current is conducted in chemical solutions. In 1883 he proposed a theory that when rock salt (which consists of sodium and chlorine) is dissolved in water, it splits into sodium atoms with positive electrical charges and chlorine atoms with negative charges. These electrically charged atoms, ions, allow the solution to conduct electricity.