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ion, in chemistry

(Encyclopedia)ion, atom or group of atoms having a net electric charge. Ionization has many applications. Vapor lamps and fluorescent lamps take advantage of the light given off when positive ions recombine with ...

formula, in chemistry

(Encyclopedia)formula, in chemistry, an expression showing the chemical composition of a compound. Formulas of compounds are used in writing the equations (see chemical equations) that represent chemical reactions....

chemistry

(Encyclopedia)chemistry, branch of science concerned with the properties, composition, and structure of substances and the changes they undergo when they combine or react under specified conditions. Organic chemi...

radical, in chemistry

(Encyclopedia)radical, in chemistry, group of atoms that are joined together in some particular spatial structure and that take part in most chemical reactions as a single unit. Important inorganic radicals include...

Iliescu, Ion

(Encyclopedia)Iliescu, Ion, 1930–, Romanian political leader, president of Romania (1990–96, 2000–2004). A member of the Communist party from 1953, he held a series of party posts before he was elected a memb...

Antonescu, Ion

(Encyclopedia)Antonescu, Ion yôn äntônĕsˈko͞o [key], 1882–1946, Romanian marshal and dictator. He served in World War I and later became chief of staff, but he fell into disfavor with King Carol II because ...

complex ion

(Encyclopedia)complex ion, charged molecular aggregate (see ion), consisting of a metallic atom or ion to which is attached one or more electron-donating molecules. In some complex ions, such as sulfate, SO4−2, t...

Bratianu, Ion

(Encyclopedia)Bratianu, Ion: see under Bratianu, family. ...

inorganic chemistry

(Encyclopedia)inorganic chemistry, the study of all the elements and their compounds with the exception of carbon and its compounds, which fall under the category of organic chemistry. Inorganic chemistry investiga...

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