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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...

protonation

(Encyclopedia)protonation prōˈtənāˌshən [key], in chemistry, addition of a proton to an atom, molecule, or ion. The proton is the nucleus of the hydrogen atom; the positive hydrogen ion, H+, consists of a sin...

nucleosynthesis

(Encyclopedia)nucleosynthesis or nucleogenesis, in astronomy, production of all the chemical elements from the simplest element, hydrogen, by thermonuclear reactions within stars, supernovas, and in the big bang at...

kamikaze

(Encyclopedia)kamikaze käˌməkäˈzē [key] [Jap.,=divine wind], the typhoon that destroyed Kublai Khan's fleet, foiling his invasion of Japan in 1281. In World War II the term was used for a Japanese suicide air...

producer gas

(Encyclopedia)producer gas, fuel gas consisting chiefly of carbon monoxide and nitrogen. It is prepared in a furnace or generator in which air is forced upward through a burning fuel of coal or coke. Although the f...

welding

(Encyclopedia)welding, process for joining separate pieces of metal in a continuous metallic bond. Cold-pressure welding is accomplished by the application of high pressure at room temperature; forge welding (forgi...

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...

chemical reaction

(Encyclopedia)chemical reaction, process by which one or more substances may be transformed into one or more new substances. Energy is released or is absorbed, but no loss in total molecular weight occurs. When, fo...

chlorine

(Encyclopedia)chlorine klōrˈēn, klôrˈ– [key] [Gr.,=green], gaseous chemical element; symbol Cl; at. no. 17; interval in which at. wt. ranges 35.446–35.457; m.p. −100.98℃; b.p. −34.6℃; density 3.2 g...

aryl group

(Encyclopedia)aryl group ârˈĭl [key], in chemistry, group of atoms derived from benzene or from a benzene derivative by removing one hydrogen that is bonded to the benzene ring (see radical). The simplest aryl g...