Columbia Encyclopedia

Search results

500 results found

nitric oxide

(Encyclopedia)nitric oxide or nitrogen monoxide, a colorless gas formed by the combustion of nitrogen and oxygen as given by the reaction: energy + N2 + O2 → 2NO; m.p. −163.6℃; b.p. −151.8℃. Nitric oxide ...

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...

Ledru-Rollin, Alexandre Auguste

(Encyclopedia)Ledru-Rollin, Alexandre Auguste älĕksäNˈdrə ôgüstˈ lədrüˈ-rôlăNˈ [key], 1807–74, French politician. A lawyer, he first became known as a radical opponent to the accession (1830) of Lou...

Palacký, František

(Encyclopedia)Palacký, František fränˈtyĭshĕk päˈlätskē [key], 1798–1876, Czech nationalist and historian, b. Moravia. Regarded as the father of the modern Czech nation, Palacký played a leading role i...

Black Hawk War

(Encyclopedia)Black Hawk War, conflict between the Sac and Fox and the United States in 1832. After the War of 1812, whites settling the Illinois country exerted pressure on the Native Americans. A treaty of 1804, ...

sting

(Encyclopedia)sting, in zoology, organ found in bees, many wasps, some ants, and in scorpions and sting rays, used defensively as well as to kill or paralyze prey. In the bee and the wasp the venom is produced by g...

transpiration

(Encyclopedia)transpiration, in botany, the loss of water by evaporation in terrestrial plants. Some evaporation occurs directly through the exposed walls of surface cells, but the greatest amount takes place throu...

school vouchers

(Encyclopedia)school vouchers, government grants aimed at improving education for the children of low-income families by providing school tuition that can be used at public or private schools. The idea behind schoo...

carbonated beverage

(Encyclopedia)carbonated beverage, an effervescent drink that releases carbon dioxide under conditions of normal atmospheric pressure. Carbonation may occur naturally in spring water that has absorbed carbon dioxid...

quinine

(Encyclopedia)quinine kwīˈnīnˌ, kwĭnēnˈ [key], white crystalline alkaloid with a bitter taste. Before the development of more effective synthetic drugs such as quinacrine, chloroquine, and primaquine, quinin...