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corrosion

(Encyclopedia)corrosion, atmospheric oxidation of metals (see oxidation and reduction). By far the most important form of corrosion is the rusting of iron. Rusting is essentially a process of oxidation in which iro...

alloy

(Encyclopedia)alloy ălˈoi, əloiˈ [key] [O. Fr.,=combine], substance with metallic properties that consists of a metal fused with one or more metals or nonmetals. Alloys may be a homogeneous solid solution, a he...

Mars, in astronomy

(Encyclopedia)Mars, in astronomy, 4th planet from the sun, with an orbit next in order beyond that of the earth. Mars has two natural satellites, discovered by Asaph Hall in 1877. The innermost of these, Phobos...

Wilkinson, Sir Geoffrey

(Encyclopedia)Wilkinson, Sir Geoffrey, 1921–, English inorganic chemist. He shared the 1973 Nobel Prize in Chemistry with Ernst Otto Fischer for their independent research on the organometallic compounds of the t...

technetium

(Encyclopedia)technetium tÄ•knēˈshÄ“É™m [key] [Gr. technetos=artificial], artificially produced radioactive chemical element; symbol Tc; at. no. 43; mass no. of most stable isotope 98; m.p. 2,200℃; b.p. 4,877â„...

plating

(Encyclopedia)plating, application of a plate, or coat, of metal to a surface for decoration, reflection of light, protection against corrosion, or increased wearing quality. The practice is of ancient origin: gild...

metallurgy

(Encyclopedia)metallurgy mĕtˈəlûrˌjē [key], science and technology of metals and their alloys. Modern metallurgical research is concerned with the preparation of radioactive metals, with obtaining metals econ...

gold

(Encyclopedia)gold, metallic chemical element; symbol Au [Lat. aurum=shining dawn]; at. no. 79; at. wt. 196.96657; m.p. 1,064.43℃; b.p. 2,808℃; sp. gr. 19.32 at 20℃; valence +1 or +3. Gold is very ductile and...

alchemy

(Encyclopedia)alchemy ălˈkəmē [key], ancient art of obscure origin that sought to transform base metals (e.g., lead) into silver and gold; forerunner of the science of chemistry. Some scholars hold that it was ...

Roseville

(Encyclopedia)Roseville. 1 City (1990 pop. 44,685), Placer co., N central Calif., a suburb of Sacramento in the foothills of the Sierra; inc. 1909. Marked by rapid growth in the late 20th cent., Roseville is in an ...