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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...

Brittany

(Encyclopedia)Brittany brĭtˈənē [key], Breton Breiz, Fr. Bretagne, region and former province, NW France. It is a peninsula between the English Channel (N) and the Bay of Biscay (S) and comprises four departmen...

weights and measures

(Encyclopedia)CE5 weights and measures, units and standards for expressing the amount of some quantity, such as length, capacity, or weight; the science of measurement standards and methods is known as metrology...

science

(Encyclopedia)science [Lat. scientia=knowledge]. For many the term science refers to the organized body of knowledge concerning the physical world, both animate and inanimate, but a proper definition would also hav...

Malta

(Encyclopedia)CE5 Malta môlˈtə [key], officially Republic of Malta, republic (2015 est. pop. 428,000), 122 sq mi (316 sq km), in the Mediterranean Sea S of Sicily. It comprises the islands of Malta (95 sq mi/...

de Gaulle, Charles

(Encyclopedia)de Gaulle, Charles shärl də gōl [key], 1890–1970, French general and statesman, first president (1959–69) of the Fifth Republic. De Gaulle was reelected to a second seven-year term in 1965. A...

nucleosynthesis

(Encyclopedia)nucleosynthesis or nucleogenesis, in astronomy, production of all the chemical elements from the simplest element, hydrogen, by thermonuclear reactions within stars, supernovas, and in the big bang at...

New Mexico

(Encyclopedia)CE5 New Mexico, state in the SW United States. At its northwestern corner are the so-called Four Corners, where Colorado, New Mexico, Arizona, and Utah meet at right angles; New Mexico is also bord...

metric system

(Encyclopedia)CE5 metric system, system of weights and measures planned in France and adopted there in 1799; it has since been adopted by most of the technologically developed countries of the world. It is based...

phosphorus

(Encyclopedia)phosphorus fŏsˈfərəs [key] [Gr.,=light-bearing], nonmetallic chemical element; symbol P; at. no. 15; at. wt. 30.97376; m.p. 44.1℃; b.p. about 280℃; sp. gr. 1.82 at 20℃; valence −3, +3, or ...