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mole, in chemistry

(Encyclopedia)mole, in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules...

dispersion, in chemistry

(Encyclopedia)dispersion, in chemistry, mixture in which fine particles of one substance are scattered throughout another substance. A dispersion is classed as a suspension, colloid, or solution. Generally, the par...

precipitation, in chemistry

(Encyclopedia)precipitation, in chemistry, a process in which a solid is separated from a suspension, sol, or solution. In a suspension such as sand in water the solid spontaneously precipitates (settles out) on st...

earth, in chemistry

(Encyclopedia)earth, in chemistry, metallic oxide not readily reducible by chemical means, e.g., alkaline earths, rare earths, and alumina. The name is also applied to certain absorbent clays, e.g., fuller's earth,...

Bratianu, Ion

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

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 ...

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...

physical chemistry

(Encyclopedia)physical chemistry, branch of science that combines the principles and methods of physics and chemistry. It provides a fundamental theoretical and experimental basis for all of chemistry, including or...

Caragiale, Ion Luca

(Encyclopedia)Caragiale, Ion Luca yŏn lo͞oˈkä käräjäˈlĭ [key], 1853–1912, Romanian playwright and author. Romania's foremost dramatist, his works sharply satirized Romanian society. His masterpiece, A Lo...

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...