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Chemistry II
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Like many Russians, Nikolai Zinin (1812-1880) looked to western Europe for the latest scientific thought. He worked with Liebig in Giessen and later took his degree in Russia. He is known for his research on reduction of nitro compounds into amino derivatives, specifically nitrobenzene into aniline, the compound shown on the Russian stamp. This work was important for the development of the aniline dye industry. |
The periodic table of elements as we know it today
was the inspired work of Dmitri Ivanovich Mendeleyev (1834-1907). His
generalization of sequences of atomic weights and properties of elements,
data already known to other scientists and arranged systematically by
them, was more than a convenient scheme positioning the elements as they
were then known; it represented to him a "law of nature," containing gaps
for elements yet undiscovered, and predicting their existence. Some of
these elements were soon found, and had indeed the properties predicted
by Mendeleyev: gallium and scandium.   |
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The following profiles of chemistry Nobel laureates
are not chronologically arranged but follow the order of the stamps in
this very attractive booklet from Sweden. All were Swedish nationals,
though some were foreign-born.
Arne Tiselius (1902-71) was proficient not only in physical chemistry, but biochemistry and some areas of medicine as well. He developed methods of analysis by adsorption particularly of colorless substances, and was awarded the 1948 Nobel prize in chemistry "for his research on electrophoresis and adsorption analysis, especially for his discoveries concerning the complex nature of the serum proteins." Born in Hungary, George de Hevesy (1885-1966) worked and studied with many notable scientists, among them Haber and Rutherford. He discovered the element hafnium with Coster while at the Institute for Theoretical Physics (Niels Bohr Institute) in Copenhagen. His most important work was "on the use of isotopes as tracers in the study of chemical processes." These processes were both in chemical reactions and also in living tissue, human and animal. Following the lead of Irene Joliot-Curie, he produced radio isotopes of phosphorus and sulfur by alpha bombardment. The Nobel prize in chemistry was awarded to him in 1943. Theodor Svedberg (1884-1971) developed the ultracentrifuge by which colloidal dispersions could be evaluated for particle size. The progressive distribution of increasingly large particles within the extremely rapidly whirling solution could be observed and recorded photographically. For this research on dispersions he received the 1926 Nobel prize in chemistry. Hans von Euler-Chelpin (1873-1964) shared the 1929 Nobel prize in chemistry with Sir Arthur Harden of Great Britain "for their investigations on the fermentation of sugar and fermentative enzymes." The fermentation process had already been investigated by Liebig and Pasteur but the contribution of enzymes in the creation of alcohol was here recognized. On the stamp, a large sugar molecule results in a smaller ethanol molecule. |
Svante Arrhenius (1859-1927) received the 1903 Nobel prize in chemistry
"in recognition of the extraordinary services he has rendered to the
advancement of chemistry by his electrolytic theory of dissociation."
This theory (Berzelius' electrochemical theory revisited) dealt with
the dissociation of salts in solution into positively and negatively
charged ions which were able to conduct a current over a potential drop.
The extent of dissociation of a substance determines its value as an
electrolyte.
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