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sublimation, in chemistry

(Encyclopedia)sublimation sŭblĭmāˈshən [key], change of a solid substance directly to a vapor without first passing through the liquid state. The term is also used to describe the reverse process of the gas ch...

suspension, in chemistry

(Encyclopedia)suspension, in chemistry, mixture of two substances, one of which is finely divided and dispersed in the other. Common suspensions include sand in water, fine soot or dust in air, and droplets of oil ...

valence, in chemistry

(Encyclopedia)valence, combining capacity of an atom expressed as the number of single bonds the atom can form or the number of electrons an element gives up or accepts when reacting to form a compound. Atoms are c...

sol, in chemistry

(Encyclopedia)sol, in chemistry: see colloid.

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...

resonance, in chemistry

(Encyclopedia)resonance, in chemistry: see chemical bond. ...

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...

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...

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 ...