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electrode

(Encyclopedia)electrode, terminal through which electric current passes between metallic and nonmetallic parts of an electric circuit. In most familiar circuits current is carried by metallic conductors, but in som...

dry cleaning

(Encyclopedia)dry cleaning, process of cleaning fabrics without water. Special solvents and soaps are used so as not to harm fabrics and dyes that will not withstand the effects of ordinary soap and water. Dry clea...

alkyl group

(Encyclopedia)alkyl group ălˈkĭl [key], in chemistry, group of carbon and hydrogen atoms derived from an alkane molecule by removing one hydrogen atom (see radical). The name of the alkyl group is derived from t...

fallout

(Encyclopedia)fallout, minute particles of radioactive material produced by nuclear explosions (see atomic bomb; hydrogen bomb; Chernobyl) or by discharge from nuclear-power or atomic installations and scattered th...

sulfide

(Encyclopedia)sulfide, chemical compound containing sulfur and one other element or sulfur and a radical. Sulfides may be salts or esters of hydrogen sulfide, H2S, or may be formed directly, e.g., by heating a meta...

biodiesel

(Encyclopedia)biodiesel, fuel made from natural, renewable sources, such as new and used vegetable oils and animal fats, for use in a diesel engine. Biodiesel has physical properties very similar to petroleum-deriv...

gunpowder

(Encyclopedia)gunpowder, explosive mixture; its most common formula, called “black powder,” is a combination of saltpeter, sulfur, and carbon in the form of charcoal. Historically, the relative amounts of the c...

Franklin, Rosalind Elsie

(Encyclopedia)Franklin, Rosalind Elsie, 1920–58, English molecular biologist and chemist, grad. Newnham College, Cambridge (1941). She spent most of the war years (1942–45) working for the British Coal Utilisat...

chemosynthesis

(Encyclopedia)chemosynthesis, process in which carbohydrates are manufactured from carbon dioxide and water using chemical nutrients as the energy source, rather than the sunlight used for energy in photosynthesis....

calcium oxide

(Encyclopedia)calcium oxide, chemical compound, CaO, a colorless, cubic crystalline or white amorphous substance. It is also called lime, quicklime, or caustic lime, but commercial lime often contains impurities, e...