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Svedberg, Theodor

(Encyclopedia)Svedberg, Theodor or The tāˈōdôr svādˈbĕryə, tā [key], 1884–1971, Swedish chemist. He was professor of physical chemistry from 1912 to 1949 at the Univ. of Uppsala. For his fundamental rese...

Wöhler, Friedrich

(Encyclopedia)Wöhler, Friedrich frēˈdrĭkh vöˈlər [key], 1800–1882, German chemist. He studied under the German chemist Leopold Gmelin and J. J. Berzelius, a Swedish chemist, and in 1836 was appointed profe...

Ramsay, Sir William

(Encyclopedia)Ramsay, Sir William, 1852–1916, Scottish chemist. He was professor of chemistry at University College, Bristol (1880–87), and at University College, London (1887–1912). In his early experiments ...

MacMillan, David W.C.

(Encyclopedia)MacMillan, David W.C., 1968–, b. Bellshill, U.K. Scotish chemist, James S. McDonnell Distiguished University Professor in Chemistry and ...

International Union of Pure and Applied Chemistry

(Encyclopedia)International Union of Pure and Applied Chemistry (IUPAC), an international organization est. 1919 to advance the chemical sciences and contribute to the application of chemistry to the service of hum...

molecular orbital theory

(Encyclopedia)molecular orbital theory, detailed explanation of how electrons are distributed in stable molecules. In the simpler valence theory of the chemical bond, each atom in a molecule is assumed to retain it...

biochemistry

(Encyclopedia)biochemistry, science concerned chiefly with the chemistry of biological processes; it attempts to utilize the tools and concepts of chemistry, particularly organic and physical chemistry, for elucida...

seaborgium

(Encyclopedia)seaborgium sēbôrˈgēəm [key], artificially produced radioactive chemical element; symbol Sg; at. no. 106; mass number of most stable isotope 271; m.p., b.p., sp. gr., and valence unknown. Situated...

Windaus, Adolf

(Encyclopedia)Windaus, Adolf äˈdôlf vĭnˈdous [key], 1876–1959, German chemist. He was professor of chemistry and director of the chemistry laboratories at the Univ. of Göttingen (1915–44). For his researc...

semiconductor

(Encyclopedia)CE5 N-type and P-type crystals: In a pure silicon crystal each silicon atom (Si) is surrounded by four valence electrons. In the N-doped semiconductor, illustrated in the left-hand figure, some sil...