2008chemistry11 - Svante August Arrhenius

Svante August Arrhenius

Personal History

On February 19th, 1859, in Wijk Sweden, a great scientist was born. Svante August Arrhenius moved to Uppalsa with his family in the year 1860, where he would eventually attend Cathedral school. Arrhenius began reading at the age of three, and already showed in interest in mathematics. His interest in math began by watching his father add columns of figures. He graduated from high school being the youngest and brightest from his class.

In 1879 he entered the University of Uppsala where he started his study of mathematics, chemistry and physics. Not inpressed with the pratical intruction in physics he swiched to Stockholm to study under the instruction of Professor E. Edlund at the Academy of Sciences 2 years later in 1881. After assisting Edlund in his work on electromotive force measurments in spark discharges, he soon decided to move on to move on to intrests of his own. In 1884 he created a thesis "Investigation on the galvanic conductivity of electrolytes." From this results he concluded a theory that he is best known for today, "electrolytes, when dissolved, in water, become to varying degrees split or dissociated into electritcally opposite positive and negative ions." To explain his theroy more clearly here is a quote (http://chem.ch.huji.ac.il/history/arrhenius.htm) :

"The degree to which this dissociation occurred depended above all on the nature of the substance and its concentration in the solution - being more developed the greater the dilution. The ions were supposed to be the carriers of the electric current, e.g. in electrolysis, but also of the chemical activity. The relation between the actual number of ions and their number at great dilution (when all the molecules were dissociated) gave a quantity of special interest ("activity constant")."
- He died at Stockholm on October 2, 1927, and is buried at Uppsala

Accomplishments, Discoveries, and Contributions

As stated above he is best known today for his theory : "electrolytes, when dissolved, in water, become to varying degrees split or dissociated into electrically opposite positive and negative ions." He has also been recognized by the professional societies and the Nobel Prize committee. He had determined the conductivity of many electrolytes and planned his dissertation proposal by the age of 24.

A possible format for his data:

Electrolyte	0.001 M	0.005 M	0.01 M	0.1 M	0.5 M
Acetic acid	41	20	6.5	4.6	2.0
Hydrochloric acid	377	373	360	351	327
Sodium acetate	75	72	64	61	49

(this is taken directly from source)
From this data he noted:

The resistance of an electrolyte is increased when the dilution is do ubled.
In very dilute solutions the conductivity is nearly proportional to the concentration.
The conductivity of a solution is equal to the sum of conductivities of the salt and the solvent.
If these laws are not observed, it must be due to a chemical reaction between the substances including the solvent.
The electrical resistance rises with increasing viscosity, complexity of the ion, and the molecular mass of the solvent. (incorrect)

Arrhenius was able to conclude from the above statements that "molecule breaks apart into a positive fragment and negative fragment, called ions, by it's interaction with the solvent." Arrhenius was a tad before his time thinking like this, but as time passed he was soon able to spread the concept of dissociation by talking with other chemists. His data is still applicable to ours today, out data still supports the concept that ionic and polar covalently bonded substances dissociate in water.

His work even impressed Wilhelm Ostwald and Jaco bus Henricus van't Hoff, who have now become the a few of the founding fathers of physical chemistry. Later he was offered a position in Riga, Latvia, by Ostwald, but due to his fathers illness he had to tuen that oppurtunity down. Luckely he was given a post in Sweden and later a travel grant from the Swedish Academy that gave him the oppurtunity to work with Ostwalk and van't Hoff.

Awards/accomplishments

Awarded a travelling fellowship from the Academy of Sciences which enabled him to work in 1886 with Ostwald in Riga and with Kohlrausch in Würzburg.
Nobel prize for chemistry
In 1895 he became Professor of Physics at Stockholms Högskola
1905 he decided to start a Nobel Institute for Physical chemistry with Arrhenius as it's chief
In 1900 Arrhenius published his Lärobok i teoretisk elektrokemi (Textbook of theoretical electrochemistry)
1906 followed Theorien der Chemie (Theories of Chemistry) and Immunochemistry and in 1918 the Silliman lectures Theories of solutions
was elected a Foreign member of the Royal Society in 1911
was awarded the Society's Davy medal and also the Faraday Medal of the Chemical Society (1914)
Among the many tokens of distinction that he received were honorary degrees from the Universities of Birmingham, Cambridge, Edinburgh, Greifswald, Groningen, Heidelberg, Leipzig and Oxford.
In 1905 he made a prediction that carbon dioxide emission from the burning of fossil fuels would cause global warming

Interesting Facts

In an extension of his ionic theory Arrhenius proposed definitions for acids and bases
neither Bronsted nor Lewis received the Nobel Prize for continuing the work on the theory of acids and bases and for expanding the definition of these substances
1889 he introduced the concept of activation energy as the critical energy that chemicals need to react
Arrhenius was a genial, energetic man who made many friends on his visits abroad
He had an excellent memory
He loved nature, and could care less about fine arts and literature
He was happy in his family life and work
He was married twice, once in 1894 to Sofia Rudbeck, and he has a son with her and in 1905 he married once again to Maria Johansson, and he had one son and two daughters with her