Columbia Encyclopedia

Search results

110 results found

alum

(Encyclopedia)alum ălˈəm [key], any one of a series of isomorphous double salts that are hydrated sulfates of a univalent cation (e.g., potassium, sodium, ammonium, cesium, or thallium) and a trivalent cation (e...

Freeport, cities, United States

(Encyclopedia)Freeport. 1 City (2020 pop. 23,973), seat of Stephenson co., NW Ill., on the Pecatonica River; inc. 1850. It is a trade and manufacturing center in a ...

water supply

(Encyclopedia)water supply, process or activity by which water is provided for some use, e.g., to a home, factory, or business. The term may also refer to the supply of water provided in this way. In the United Sta...

electromotive series

(Encyclopedia)electromotive series, list of metals whose order indicates the relative tendency to be oxidized, or to give up electrons (see oxidation and reduction); the list also includes the gas hydrogen. The ele...

hafnium

(Encyclopedia)hafnium hăfˈnēəm [key], metallic chemical element; symbol Hf; at. no. 72; at. wt. 178.49; m.p. about 2,227℃; b.p. 4,602℃; sp. gr. 13.31 at 20℃; valence +4. Hafnium is a lustrous, ductile, si...

rare-earth metals

(Encyclopedia)rare-earth metals, in chemistry, group of metals including those of the lanthanide series and actinide series and usually yttrium, sometimes scandium and thorium, and rarely zirconium. Promethium, whi...

Henderson

(Encyclopedia)Henderson. 1 City (2020 pop. 27,801), seat of Henderson co., NW Ky., on the Ohio River, in an oil, coal, tobacco, corn, and livestock area; founded ...

Great Salt Lake

(Encyclopedia)Great Salt Lake, shallow body of saltwater, NW Utah, between the Wasatch Range on the east and the Great Salt Lake Desert on the west; largest salt lake in North America. Fed by the Weber, Jordan, and...

gum, colloidal plant substance

(Encyclopedia)gum, term commonly applied to any of a wide variety of colloidal substances somewhat similar in appearance and general characteristics, exuded by or extracted from plants. In this classification, howe...

mantle

(Encyclopedia)mantle, portion of the earth's interior lying beneath the crust and above the core. No direct observation of the mantle, or its upper boundary, has been made; its boundaries have been determined solel...