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Pfeffer, Wilhelm

(Encyclopedia)Pfeffer, Wilhelm vĭlˈhĕlm pfĕˈfər [key], 1845–1920, German plant physiologist. He was professor of botany successively at the universities of Bonn, Basel, Tübingen, and Leipzig (from 1887). W...

law of simple multiple proportions

(Encyclopedia)law of simple multiple proportions, in chemistry, the statement that when two or more elements form more than one compound, the ratio of the weights of one element that combine with a given weight of ...

Boyle, Robert

(Encyclopedia)Boyle, Robert, 1627–91, Anglo-Irish physicist and chemist. The seventh son of the 1st earl of Cork, he was educated at Eton and on the Continent and conducted most of his researches at his own labor...

N

(Encyclopedia)N, 14th letter of the alphabet. It is a usual symbol for a voiced alveolar (or dental) nasal, as in the English not. The diagraph ng represents a different sound, a voiced velar nasal, as in the Engli...

Marggraf, Andreas Sigismund

(Encyclopedia)Marggraf, Andreas Sigismund ändrāˈäs zēˈgĭsmo͝ont märkˈgräfˌ [key], 1709–82, German chemist, a pioneer in analytical chemistry. He proved that alumina, magnesia, and lime are distinct ea...

Kuhn, Richard

(Encyclopedia)Kuhn, Richard rĭkhˈärt ko͞on [key], 1900–1967, Austrian chemist, director of the Kaiser Wilhelm Institute, Heidelberg. For his research on the carotinoids (he prepared eight of them in pure form...

S

(Encyclopedia)S, 19th letter of the alphabet, representing the common sibilant, voiceless in spur, voiced in rose. Its Greek equivalent is sigma. In former times the nonterminal s was written or printed much like a...

Abel, Sir Frederick Augustus

(Encyclopedia)Abel, Sir Frederick Augustus, 1826–1902, English chemist, an authority on explosives. He was professor of chemistry at the Royal Military Academy (1851–55) and chemist to the War Dept. and governm...

Chaptal, Jean Antoine

(Encyclopedia)Chaptal, Jean Antoine zhäN äNtwänˈ shäptälˈ [key], 1756–1832, French chemist, industrialist, and statesman. He became (1781) professor of chemistry at Montpellier, and during the Revolution h...

V

(Encyclopedia)V, 22d letter of the alphabet (see U). It is a usual symbol for a voiced labiodental spirant, as in the English vat. In Roman numerals it corresponds to Arabic 5. In chemistry V is the symbol of the e...