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saturation, of an organic compound

(Encyclopedia)saturation, of an organic compound, condition occurring when its molecules contain no double or triple bonds and thus cannot undergo addition reactions. For example, ethane (H3C–CH3) is a saturated ...

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...

magnesite

(Encyclopedia)magnesite măgˈnəsīt [key], mineral, magnesium carbonate, MgCO3, white, yellow, or gray in color. It originates through the alteration of olivine or of serpentine by waters carrying carbon dioxide;...

atomic mass unit

(Encyclopedia)atomic mass unit or amu, in chemistry and physics, unit defined as exactly 1⁄12 the mass of an atom of carbon-12, the isotope of carbon with six protons and six neutrons in its nucleus. One amu is e...

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...

buckyball

(Encyclopedia)buckyball, colloquial term for buckminsterfullerene, a roughly spherical fullerene molecule consisting of 60 carbon atoms. Buckytube is a generic term for cylindrical fullerenes. ...

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...

oxide

(Encyclopedia)oxide, chemical compound containing oxygen and one other chemical element. Oxides are widely and abundantly distributed in nature. Water is the oxide of hydrogen. Silicon dioxide is the major componen...

hydrocarbon

(Encyclopedia)hydrocarbon hīˌdrōkärˈbən [key], any organic compound composed solely of the elements hydrogen and carbon. The hydrocarbons differ both in the total number of carbon and hydrogen atoms in their ...

hydrogenation

(Encyclopedia)hydrogenation hīdrôjˈənāˌshən, hīˌdrəjənāˈshən [key], chemical reaction of a substance with molecular hydrogen, usually in the presence of a catalyst. A common hydrogenation is the harde...