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oxidation and reduction

(Encyclopedia)oxidation and reduction, complementary chemical reactions characterized by the loss or gain, respectively, of one or more electrons by an atom or molecule. Originally the term oxidation was used to re...

hydroxide

(Encyclopedia)hydroxide hīdrŏkˈsīd [key], chemical compound that contains the hydroxyl (−OH) radical. The term refers especially to inorganic compounds. Organic compounds that have the hydroxyl radical as a f...

amino group

(Encyclopedia)amino group, in chemistry, functional group that consists of a nitrogen atom attached by single bonds to hydrogen atoms, alkyl groups, aryl groups, or a combination of these three. An organic compound...

fullerene

(Encyclopedia)fullerene, any of a class of carbon molecules in which the carbon atoms are arranged into 12 pentagonal faces and 2 or more hexagonal faces to form a hollow sphere, cylinder, or similar figure. The sm...

Fischer, Ernst Otto

(Encyclopedia)Fischer, Ernst Otto, 1918–2007, German chemist, Ph.D. Technical Univ. of Munich (TUM), 1952. Fischer was a professor at TUM (1954–57) and the Univ. of Munich (1957–64). He returned to TUM in 196...

Hamden

(Encyclopedia)Hamden, town (2020 pop. 61,169), New Haven co., S Conn.; inc. 1786. The town, settled c.1638, was named for John Hampden, the ...

Novara

(Encyclopedia)Novara nōväˈrä [key], city (1991 pop. 101,112), capital of Novara prov., Piedmont, N Italy. It is an agricultural and industrial center and a rail junction. Manufactures include textiles, chemical...

Massa, city, Italy

(Encyclopedia)Massa mäsˈä [key], city (1991 pop. 66,737), capital of Massa-Carrara prov., Tuscany, N central Italy, near the Ligurian Sea. Marble is quarried, and chemicals, metals, and machinery are produced th...

rare earths

(Encyclopedia)rare earths, in chemistry, oxides of the rare-earth metals. They were once thought to be elements themselves. They are widely distributed in the earth's crust and are fairly abundant, although they we...

Vannes

(Encyclopedia)Vannes vän [key], town (1990 pop. 48,454), capital of Morbihan dept., NW France, in Brittany, on the Gulf of Morbihan. It is an important agricultural and tourist center that produces processed food,...