ScienceWeek

WILHELM OSTWALD (1852-1932)

The following points are made by J. Van Houten (J. Chem Ed. 2002 79:146):

1) It seems fitting that Wilhelm Ostwald should receive the Nobel Prize in 1909 for his work in chemical dynamics shortly after the awards to J. van't Hoff (1852-1911) and S. Arrhenius (1859-1927) because both of them had studied with Ostwald -- as what we would now call post-doctoral fellows. Another Nobel Laureate, Walther Nernst (1864-1941), winner of the 1920 chemistry Nobel Prize "for his work in thermochemistry", also worked with Ostwald in Leipzig.

2) Ostwald and van't Hoff are regarded together as the founders of the discipline of modern physical chemistry. Ostwald organized the Department of Physical Chemistry at Leipzig University; he founded the Deutsche Elektrochemische Gesellschaft (German Electrochemical Society) in 1894, which expanded to become the Deutsche Bunsen-Gesellschaft fuer Angewandte Physikalische Chemie (German Bunsen-Society for Applied Physical Chemistry) in 1902. Ostwald and van't Hoff together founded the first journal in physical chemistry, Zeitschrift fuer Physikalische Chemie in 1887, and Ostwald himself edited the first 100 volumes, until 1922.

3) Ostwald's work served to validate the catalytic theories of J. Berzelius (1779-1848) as well as Berzelius's theories of acid and base dissociation. In particular, Ostwald observed that the rates of reactions with acids and bases could be related to the strengths of those acids and bases. Thus Ostwald laid the groundwork for systematic study of reaction kinetics and of catalysis. In addition, Ostwald utilized conductivity measurements to confirm Arrhenius's theories regarding ionic dissociation of acids and bases. In particular he showed that weak acids and bases were incompletely ionized in solution -- the concept that we now associate with pKa. By correlating his results from kinetic studies with his conductivity studies, Ostwald concluded that the effect of acids and bases in determining reaction rates was directly related to the hydrogen ion or hydroxide ion concentration, hence the strength, of the acid or base.

4) As a result of his study of various catalytic processes, Ostwald developed the principle that a catalyst can modify the rate of a reaction without any net change in the catalytic material itself over the full course of the reaction. At the time Ostwald received the Nobel Prize in 1909, the importance of catalysts was just becoming widely recognized. Thus his Nobel presentation includes the statement:

"The significance of this new idea is best revealed by the immensely important role --first pointed out by Ostwald -- of catalytic processes in all sectors of chemistry. Catalytic processes are a commonplace occurrence, especially in organic synthesis. Key sections of industry ... are based on the action of catalysts. A factor of perhaps even greater weight, however, is the growing realization that the enzymes, so-called, which are extremely important for the chemical processes within living organisms, act as catalysts and hence the theory of plant and animal metabolism falls essentially in the field of catalyst chemistry".

Ostwald first proved the catalytic action of enzymes in 1893.