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cobalt, chemical element

(Encyclopedia)cobalt, metallic chemical element; symbol Co; at. no. 27; at. wt. 58.9332; m.p. 1,495℃; b.p. about 2,870℃; sp. gr. 8.9 at 20℃; valence +2 or +3. Cobalt is a silver-white, lustrous, hard, brittle...

solution

(Encyclopedia)CE5 Solubility curves solution, in chemistry, homogeneous mixture of two or more substances. The dissolving medium is called the solvent, and the dissolved material is called the solute. A solutio...

Piatra-Neamţ

(Encyclopedia)Piatra-Neamţ pyäˈträ-nyämts [key], city (1990 pop. 118,216), NE Romania, in the Bacău region. Food processing, and the manufacture of fertilizers, furniture, ceramics, and paper are among the in...

ligand

(Encyclopedia)ligand lĭgˈənd [key], charged or uncharged molecule with one or more unshared pairs of electrons that can attach to a central metallic atom or ion to form an aggregate known as a complex ion (see c...

nonmetal

(Encyclopedia)nonmetal, chemical element possessing certain properties by which it is distinguished from a metal. In general, this distinction is drawn on the basis that a nonmetal tends to accept electrons and for...

carbonate

(Encyclopedia)carbonate kärˈbənātˌ, –nət [key], chemical compound containing the carbonate radical or ion, CO3−2. Most familiar carbonates are salts that are formed by reacting an inorganic base (e.g., a ...

Goodenough, John Bannister

(Encyclopedia)Goodenough, John Bannister, 1922–2023, American physicist, b. Jena, Germany, Ph.D. Univ. of Chicago, 1952. Goodenough was a researcher at the Massachu...

liquid air

(Encyclopedia)liquid air, ordinary air that has been liquefied by compression and cooling to extremely low temperatures (see liquefaction). Its commercial preparation involves purification by washing to remove solu...

Fehling's solution

(Encyclopedia)Fehling's solution fāˈlĭngz [key], deep-blue, alkaline solution used to test for the presence of aldehydes (e.g., formaldehyde, HCHO) or other compounds that contain the aldehyde functional group, ...

deuterium

(Encyclopedia)deuterium do͞otērˈēəm [key], isotope of hydrogen with mass no. 2. The deuterium nucleus, called a deuteron, contains one proton and one neutron. Deuterium is also called heavy hydrogen, and water...