Columbia Encyclopedia

Search results

493 results found

tar and pitch

(Encyclopedia)tar and pitch, viscous, dark-brown to black substances obtained by the destructive distillation of coal, wood, petroleum, peat, and certain other organic materials. The heating or partial burning of w...

Titicaca

(Encyclopedia)Titicaca tētēkäˈkä [key], lake, c.3,200 sq mi (8,290 sq km), 110 mi (177 km) long, and c.900 ft (270 m) deep at at its deepest point, in the Andes Mts., on the Bolivia-Peru border; second largest...

ytterbium

(Encyclopedia)ytterbium ĭtûrˈbēəm [key] [for Ytterby, a town in Sweden], metallic chemical element; symbol Yb; at. no. 70; at. wt. 173.054; m.p. 819℃; b.p. about 1,194℃; sp. gr. about 7.0; valence +2 or +3...

boric acid

(Encyclopedia)boric acid, any one of the three chemical compounds, orthoboric (or boracic) acid, metaboric acid, and tetraboric (or pyroboric) acid; the term often refers simply to orthoboric acid. The acids may be...

molecular weight

(Encyclopedia)molecular weight, weight of a molecule of a substance expressed in atomic mass units (amu). The molecular weight may be calculated from the molecular formula of the substance; it is the sum of the ato...

osmosis

(Encyclopedia)osmosis ŏzmōˈsĭs [key], transfer of a liquid solvent through a semipermeable membrane that does not allow dissolved solids (solutes) to pass. Osmosis refers only to transfer of solvent; transfer o...

sunspots

(Encyclopedia)sunspots, dark, usually irregularly shaped spots on the sun's surface that are actually solar magnetic storms. The spots are darker because the temperature of the spots is lower than that of the surro...

Uranus , in astronomy

(Encyclopedia)Uranus yo͝orāˈnəs, yo͝orˈə– [key], in astronomy, 7th planet from the sun, at a mean distance of 1.78 billion mi (2.87 billion km), with an orbit lying between those of Saturn and Neptune; its...

sound

(Encyclopedia) CE5 Sound waves: An air pressure wave radiating outward from a loudspeaker is perceived as sound. sound, any disturbance that travels through an elastic medium such as air, ground, or water to be ...

monotreme

(Encyclopedia)monotreme mŏnˈətrēmˌ [key], name for members of the primitive mammalian order Monotremata, found in Australia, Tasmania, and New Guinea. The only members of this order are the platypus, or duckbi...
 

Browse by Subject