Svante Arrhenius

Svante August Arrhenius ( pronunciation: [ ˌ ː tə svan aɹe niɵs ː ]; born February 19, 1859 Good Wik at Uppsala; † October 2, 1927 in Stockholm) was a Swedish physicist and chemist and Nobel laureate in Chemistry. Arrhenius has shown that dissolved salts present in water as ions. The salts break down in the water is often not completely into ions, but - depending on the concentration - to a certain percentage; Arrhenius coined the word for this activity coefficient.

• 2.1 Electrolytic dissociation
• 2.2 kinetics
• 2.3 Meteorology and Geophysics
• 2.4 Physiology
• 2.5 cosmology

Life

Origin

Svante August Arrhenius was born the son of Svante Arrhenius Georg (1813-1885) and his wife Carolina Christina (born Thunberg ) ( 1820-1906 ) on the Good Wik Lake Mälaren. The father worked as a surveyor and was later " Academy Vogt " at Uppsala University, at which he himself had studied. The poor pay this item, let assume the office of the Administrator on the estate not far from Uppsala him additionally. The young Svante spent only a short time in the early sixties, the family moved to Uppsala. The wage of the father had been bolstered and made the second appointment superfluous as an administrator.

Vocational and academic education

Svante August was an unusually gifted child. At the age of three years, he learned to read and was in the period following an excellent mental arithmetic. At eight, he attended the Cathedral School to Uppsala, where he distinguished himself particularly in mathematics and physics. In 1876 Arrhenius completed his high school and began studying mathematics and science at the University of Uppsala. At this time Robert Tobias taught there Thalén physics. The ratio of Arrhenius to his teacher turned out to be difficult, which is one reason was why he moved to the University of Stockholm in 1881. There he became acquainted with Erik Edlund, who encouraged his talented pupil soon. 1884 doctorate Arrhenius, with the drawn up in French doctoral thesis Recherches sur la conductibilité galvanique of Electrolytes. This had already Arrhenius ' big issue to content, the electrolytic dissociation.

The scientist could then not imagine that in aqueous solutions free, unbound atoms ( with a corresponding charge ) may be present. Cooking salt (sodium chloride) was " of chlorine and sodium ." Sodium and chlorine atoms are highly reactive and it appeared at that time is highly unlikely that these atoms could move freely in the solution, because the smell of chlorine would have had to be detected. Although the assessment of his dissertation was very poor and failed him opened no way for advanced habilitation, won his theory nevertheless a weighty advocate. Wilhelm Ostwald had been able to confirm the statements made by Arrhenius considerations at the Polytechnic Institute in Riga experimentally and personally came to Stockholm to meet the young scientist. Ostwald offered Arrhenius a professorship in Riga, the first of these could not accept because of a serious illness of his father.

Follow the directions

Soon Arrhenius received a generous travel grant of the Swedish Academy of Sciences, which led him in the coming years by large parts of Europe. First he followed Ostwald to Riga and then worked from 1886 with Friedrich Kohlrausch in Würzburg, where he became acquainted with the doctoral students Walther Nernst. Since that visit, the physicist Kohlrausch opened up vast areas of a new physical chemistry.

Then his way led him to Ludwig Boltzmann in Graz (1887 ) and further to van't Hoff to Amsterdam, then turn to Ostwald, who is now teaching in Leipzig (both 1888). After a short stay in his home Arrhenius worked in 1889/90 again in Leipzig and Graz. These stations decided the perennial wandering life, because in 1891 took a job as Arrhenius ' Laborator of Physics " at the University of Stockholm.

A professor at Giessen, which had also been offered to him, he struck out. 1895 his post was converted into a professorship, which he finally 1905 - has already been honored with the Nobel Prize for Chemistry (1903 ) - gave up in favor of the Nobel Institute for Physical Chemistry, whose director he was.

End of life

In the higher age Arrhenius was forced due to its numerous offices to invest much effort in administrative tasks. To be able to still devote the research and publication work, he did not spare his life robust health. For the work on a new edition of The Evolution of the worlds he stood for example, in the autumn of 1925 a day at four clock. However, the end of the year, he suffered a dizzy spell, from which he never quite recovered. In the spring of 1927 Arrhenius resigned as director of the Nobel Institute and wrote in the summer of his unfinished memoirs. The end of September he fought with acute enteritis, the consequences of which he died on 2 October 1927. He was buried according to his wish in Uppsala, the city of his youth.

Progeny

Arrhenius was married twice. His first wife was Maria Margareta 1894 Brita Sophia Rudbeck. With her he had a son, Olof Arrhenius (* November 2, 1895, † May 8, 1977 ) biochemist. The marriage was but divorced in 1896. His second wife in 1905 Maria Johansson ( 1871-1957 ). The couple had a son Sven (1909-1991) and two daughters.

Scientific work

Arrhenius was a very versatile scientist, who conducted research in such diverse fields as physical chemistry, meteorology, geophysics, physiology and cosmology. When his most important achievement the development of the foundations of electrolytic dissociation is considered.

Electrolytic dissociation

Arrhenius made ​​, in particular, the theory of electrolytic dissociation deserves.

The work of van't Hoff, by means of which he had deviations from a calculated molecular composition found by measuring the ebullioscopic properties in liquids eg steam pressure increase and decrease the freezing point for acids, bases and salts, confirmed the theory of Arrhenius. Richard Abegg was able to demonstrate that potassium chloride actually had to be dissociated into ions and the Dissoziationswerte from freezing point depressions in good agreement with the conductivity measurements at equal concentrations by accurate measurements of aqueous sucrose and potassium chloride solutions.

To the knowledge of these writings Arrhenius made ​​a short article to illustrate the dissociation theory of Arrhenius used .. In this work, instead of the word Dissoziationskoeffizient the word Aktivitätskoeffizent. The dissociated cleavage products of a salt are the ions and the activity coefficient indicates the proportion of the ions at in relation to all particles of this sort. Arrhenius comes from the conductivity measurements further concluded that aims at very high dilution the activity coefficient to 1, and thus all salts, acids, bases are completely dissociated into ions in highly dilute solutions. In concentrated solutions, the activity coefficient is less than 1, that is not all the salt particles, acids, bases are dissociated into ions.

Arrhenius conductivity measurements were for a simple formula to determine the degree of dissociation of 1,1- electrolytes to:

Thereby the degree of dissociation is ( activity coefficient ) of the salt ( acid, base), the molar equivalent conductivity, the boundary conductivity at infinite dilution.

Arrhenius also assumes that each ion in the salt plays a special, individual character conductivity. In salt mixtures of these special character of each ion conductivity must be determined. We know these rule today as the limiting equivalent conductivity of the ions at infinite dilution.

Kinetics

The dependence of the conductivity of electrolytes with the temperature had indeed been thoroughly investigated by Kohlrausch after his first meeting with Arrhenius, but he could find that some electrolytes react when the temperature increases with a decrease in conductivity.

The influence of the reaction rate by the concentrations of the ions involved and temperature was another theme of his work 1889. Temperature affects exponentially the reaction rate of ions whose concentration he could control by conductivity measurements. The method of analysis by means of the Arrhenius equation is generally accepted.

Meteorology and Geophysics

But Arrhenius also conducted research on topics of the atmosphere and meteorology such as over the northern lights, storms and climate variability. He suspected that cosmic radiation pressure is transported across the room, thus leading to light phenomena such as the aurora borealis. He presented in 1895 before a theory of greenhouse effect. Carbon dioxide could absorb the infra-red heat rays of light emitted by the earth and by much carbon dioxide the earth's climate could heat up. In particular, by increased volcanic activity, the carbon dioxide content of the atmosphere could increase, so that there could be a rise in temperature. He also assumed that the content of water vapor in the atmosphere WOULD in a same direction as carbon dioxide and thus could enhance the result. The vegetation should act in his opinion, than carbon dioxide regulator. In the history of research of climate change, therefore, it takes an important place. He won from the human, reinforcing influence on the greenhouse effect mostly positive sides: " The rise in CO2 will allow you to live in a warmer future sky people. "

Physiology

Arrhenius explored with staff and the immunochemistry and wrote a book about it. However, his theories were in contradiction to Paul Ehrlich's views on immunochemistry.

Cosmology

Arrhenius dealt at great length with problems of cosmology. He founded in 1906 the pangenesis, in which the hypothesis is represented that life has passed through meteorites on Earth. He believed that spores could be transferred between planets. This idea was taken up later by the English astronomer Fred Hoyle once again. In 1903 he published his Textbook of cosmic physics.

Honors

Arrhenius was a member of many academies and scientific societies in Sweden and abroad, including the Royal Society of Sciences in Uppsala (since 1899), the Royal Physio Graphic Society in Lund (since 1900), the Royal Swedish Academy of Sciences (since 1901), the Norwegian Academy of Sciences (since 1902) and the Royal Danish Academy of Sciences and the Kungliga Vetenskaps -och Vitterhetssamhället i Göteborg (since 1903). 1904 Arrhenius was made an honorary member of the Association of Swedish physicians and 1920, the Royal Swedish Academy of Engineering Sciences. In 1902 he received the Davy Medal of the Royal Society in London.

On August 8, 1903, the Medical Faculty of Heidelberg University Svante Arrhenius awarded an honorary doctorate. A few weeks later he was " ... in recognition of the extraordinary services he has rendered by his theory of electrolytic dissociation to the development of chemistry " as the first Swede the Nobel Prize for Chemistry. Also the universities of Cambridge, Oxford, Greifswald, Leipzig, Groningen, Edinburgh and Birmingham awarded him honorary doctorates.

A moon crater and an asteroid named after him.