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trinitrotoluene

(Encyclopedia)trinitrotoluene or TNT trīˌnīˌtrōtŏlˈyo͞oēn [key], CH3C6H2(NO2)3, crystalline, aromatic compound that melts at 81℃. It is prepared by the nitration of toluene. Trinitrotoluene is a high exp...

solder

(Encyclopedia)solder sŏdˈər [key], metal alloy used in the molten state as a metallic binder. The type of solder to be used is determined by the metals to be united. Soft solders are commonly composed of lead an...

rare earths

(Encyclopedia)rare earths, in chemistry, oxides of the rare-earth metals. They were once thought to be elements themselves. They are widely distributed in the earth's crust and are fairly abundant, although they we...

hydrogen chloride

(Encyclopedia)hydrogen chloride, chemical compound, HCl, a colorless, poisonous gas with an unpleasant, acrid odor. It is very soluble in water and readily soluble in alcohol and ether. It fumes in moist air. It is...

germanium

(Encyclopedia)germanium jərmāˈnēəm [key] [from Germany], semimetallic chemical element; symbol Ge; at. no. 32; at. wt. 72.63; m.p. 937.4℃; b.p. 2,830℃; sp. gr. 5.323 at 25℃; valence +2 or +4. Pure german...

alizarin

(Encyclopedia)alizarin əlĭzˈərĭn [key], or 1,2-dihydroxyanthraquinone, mordant vegetable dye obtained originally from the root of the madder plant (Rubia tinctorum), in which it occurs as a glucoside. The term...

Alès

(Encyclopedia)Alès älāˈ, älĕsˈ [key], city, Gard dept., S France, in Languedoc, at the foot of the Cévennes Mts., on the Gardon River. Once noted for cloth and silk, its industr...

Englewood

(Encyclopedia)Englewood ĕngˈgəlwo͝od [key]. 1 City (2020 pop. 33,659), Arapahoe co., N central Colo., o...

Everett

(Encyclopedia)Everett. 1 City (2020 pop. 49,075), Middlesex co., E Mass., an industrial suburb of Boston, on the Mystic River; settled c.1643, set off ...

Ewing, Sir James Alfred

(Encyclopedia)Ewing, Sir James Alfred yo͞oˈĭng [key], 1855–1935, Scottish engineer and physicist. As professor at Tokyo (1878–83), Dundee (1883–90), and Cambridge (1890–1903), he helped establish program...