Columbia Encyclopedia

Search results

428 results found

photosynthesis

(Encyclopedia)photosynthesis fōˌtōsĭnˈthəsĭs [key], process in which green plants, algae, and cyanobacteria utilize the energy of sunlight to manufacture carbohydrates from carbon dioxide and water in the pr...

dry ice

(Encyclopedia)dry ice: see carbon dioxide.

hiccup

(Encyclopedia)hiccup or hiccough, involuntary spasmodic contraction of the diaphragm followed by a sharp intake of air, which is abruptly stopped by a sudden, involuntary closing of the glottis (opening between the...

soda water

(Encyclopedia)soda water, a solution of carbon dioxide in water. ...

coal gas

(Encyclopedia)coal gas, gas obtained in the destructive distillation of soft coal, as a byproduct in the preparation of coke. Its composition varies, but in general it is made up largely of hydrogen and methane wit...

heterotroph

(Encyclopedia)heterotroph hĕtˈərətrōfˌ [key], living organism that obtains its energy from carbohydrates and other organic material. All animals and most bacteria and fungi are heterotrophic. In contrast, aut...

heat of combustion

(Encyclopedia)heat of combustion, heat released during combustion. In particular, it is the amount of heat released when a given amount (usually 1 mole) of a combustible pure substance is burned to form incombustib...

water gas

(Encyclopedia)water gas, colorless poisonous gas that burns with an intensely hot, bluish (nearly colorless) flame. The gas is a mixture of carbon monoxide and hydrogen with very small amounts of other gases, e.g.,...

Fischer-Tropsch process

(Encyclopedia)Fischer-Tropsch process fĭshˈər-trōpsh [key], method for the synthesis of hydrocarbons and other aliphatic compounds. Synthesis gas, a mixture of hydrogen and carbon monoxide, is reacted in the pr...

peat

(Encyclopedia)peat, soil material consisting of partially decomposed organic matter, found mainly in swamps and bogs in various parts of the northern temperate zone but also in some semitropical and tropical region...