Columbia Encyclopedia
Search results
37 results found
tranquilizer
(Encyclopedia)tranquilizer, drug whose action calms the central nervous system, decreasing emotional agitation without impairing alertness. Tranquilizing drugs differ from hypnotic drugs such as barbiturates in tha...hydrogen bomb
(Encyclopedia)hydrogen bomb or H-bomb, weapon deriving a large portion of its energy from the nuclear fusion of hydrogen isotopes. In an atomic bomb, uranium or plutonium is split into lighter elements that togethe...mica
(Encyclopedia)mica mīˈkə [key], general term for a large group of minerals, hydrous silicates of aluminum and potassium, often containing magnesium, ferrous iron, ferric iron, sodium, and lithium and more rarely...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...Atacama Desert
(Encyclopedia)Atacama Desert ätäkäˈmä [key], arid region, c.600 mi (970 km) long, N Chile, extending south from the border of Peru. The desert itself, c.2,000 ft (610 m) above sea level, is a series of dry sal...actinium
(Encyclopedia)actinium ăktĭnˈēəm [key] [Gr.,=like a ray], radioactive chemical element; symbol Ac; at. no. 89; mass number of most stable isotope 227; m.p. about 1,050℃; b.p. 3,200℃±300℃; sp. gr. 10.07;...cesium
(Encyclopedia)cesium sēˈzēəm [key] [Lat.,=bluish gray], a metallic chemical element; symbol Cs; at. no. 55; at. wt. 132.90545; m.p. 28.4℃; b.p. 669.3℃; sp. gr. 1.873 at 20℃; valence +1. Cesium is a ductil...fuel
(Encyclopedia)fuel, material that can be burned or otherwise consumed to produce heat. The common fuels used in industry, transportation, and the home are burned in air. The carbon and hydrogen in fuel rapidly comb...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...depression, in psychiatry
(Encyclopedia)depression, in psychiatry, a symptom of mood disorder characterized by intense feelings of loss, sadness, hopelessness, failure, and rejection. The two major types of mood disorder are unipolar disord...Browse by Subject
- Earth and the Environment +-
- History +-
- Literature and the Arts +-
- Medicine +-
- People +-
- Philosophy and Religion +-
-
Places
+-
- Africa
- Asia
- Australia and Oceania
- Britain, Ireland, France, and the Low Countries
- Commonwealth of Independent States and the Baltic Nations
- Germany, Scandinavia, and Central Europe
- Latin America and the Caribbean
- Oceans, Continents, and Polar Regions
- Spain, Portugal, Italy, Greece, and the Balkans
- United States, Canada, and Greenland
- Plants and Animals +-
- Science and Technology +-
- Social Sciences and the Law +-
- Sports and Everyday Life +-
