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Svante August Arrhenius
The Swedish chemist and physicist Svante August Arrhenius (1859-1927) is known for his theory of electrolytic dissociation.
Svante Arrhenius was born on Feb. 19, 1859, at Vik near Uppsala, the son of Svante Gustav and Carolina Thunberg Arrhenius. His father was a land surveyor and later a supervisor at the University of Uppsala.
Arrhenius's intellectual abilities became obvious early. Against his parents' wishes, the blond, blue-eyed, rubicund child taught himself to read at the age of 3. He acquired a fantastic arithmetical skill and a pictorial memory by observing his father adding columns in his account books. In his future scientific work, he was especially fond of discovering relationships and laws from masses of data. At the age of 8, he entered the fifth grade of the cathedral school, where he distinguished himself particularly in physics and mathematics and from which he graduated, the youngest and ablest student, in 1876.
Theory of Electrolytes
Arrhenius entered the University of Uppsala, where he studied chemistry, physics, and mathematics. As he was not satisfied with his chief instructor in physics, he left Uppsala in 1881 to work on the conductivities of electrolytes at Stockholm under the physicist E. Edlund. In 1884 Arrhenius presented his results (Recherches sur la conductibilité galvanique des électrolytes) together with a new theory of electrolytes (Théorie chimique des électrolytes) in a 150-page dissertation for the doctorate at Uppsala. Although he compromised and moderated his radical ideas, his professors were not impressed and only grudgingly passed the dissertation.
Arrhenius's theory of electrolytes encountered widespread resistance from the scientific world, but it eventually found confirmation in the modern theory of atomic structure. Of the 56 theses advanced in his 1884 dissertation, only a few have not withstood the test of time or have had to be greatly modified. In order to explain the nonconductance of solid salt and pure water when tested separately and the conductance of an aqueous salt solution, Arrhenius postulated that when a solid salt is dissolved in water its molecules dissociate or ionize into charged particles, which Michael Faraday had called ions years before. Whereas Faraday assumed that such ions are produced only during electrolysis, Arrhenius proposed that they are already present in solution even without the application of an electric current. Chemical reactions in solutions are thus reactions between ions. Arrhenius's views were essentially correct for weak electrolytes (weak acids, bases, and other covalent substances), but for strong electrolytes his ideas were modified in 1923 by the Debye-Hückel theory of inter-ionic attraction.
Professional Recognition
With the aid of a travel grant from the Swedish Academy of Sciences, Arrhenius devoted his next few years to travel and study. He worked with Wilhelm Ostwald in Riga and Leipzig, with Friedrich Kohlrausch in Würzburg, with Ludwig Boltzmann in Graz, and with J. H. van't Hoff in Amsterdam.
In 1891 Arrhenius was appointed lecturer and in 1895, over strong objections, professor of physics at the Technical University of Stockholm, of which he became rector in 1896. During this time he courted and married Sofia Rudback. The couple had a son, Olav Vilhelm, who became a worker in soil science and agricultural botany. Three children were born of his second marriage, to Maria Johansson.
In 1901 Arrhenius was elected, with strong opposition, to th Swedish Academy of Sciences. The following year he received the Davy Medal of the Royal Society, and in 1903 he became the first Swede to receive the Nobel Prize in chemistry for his theory of electrolytic dissociation. He was appointed rector of the newly founded Nobel Institute for Physical Research at Stockholm in 1905, a position he held until his retirement in the spring of 1927.
Spectrum of Scientific Achievement
After his theory was accepted by the entire scientific world, Arrhenius turned his attention to other topics. He became interested in the widest application of the fundamental theory of chemical reactions. In 1902 he began to apply the laws of theoretical chemistry to physiological problems, especially those of serum therapy (immunochemistry). He found that organismic changes follow the same laws as ordinary chemical reactions and that no essential difference exists between reactions in the test tube and those in the human body.
Arrhenius became active in the fields of astronomy and cosmic physics, and he proposed a new theory of the birth of the solar system by the collision of stars. He used the ability of radiation pressure to transport cosmic material to explain comets, the corona, the aurora borealis, and zodiacal light. He also hypothesized that spores of living matter are transported by radiation pressure from planet to planet with the resultant spread of life throughout interstellar space. He developed a theory to explain the ice ages and other profound climatic changes undergone by the earth's surface. He reflected upon the world's supply of energy and the conservation of natural resources. He dreamed of a universal language and proposed a modified form of English. There was hardly a field of science to which he did not make original, if not universally accepted, contributions. During his last years he wrote several textbooks and many books of a popular nature, in which he made it a point to indicate what was still to be done in the fields under discussion. Arrhenius had a healthy constitution, but he made great demands upon himself in order to maintain his extraordinary productivity. After a brief attack of acute intestinal catarrh in September 1927, he died on October 2 and was buried in Uppsala.
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