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europium

(Encyclopedia)europium yo͝orōˈpēəm [key] [from Europe], metallic chemical element; symbol Eu; at. no. 63; at. wt. 151.964; m.p. about 820℃; b.p. about 1,600℃; sp. gr. 5.25 at 25℃; valence +2 or +3. Europ...

terbium

(Encyclopedia)terbium tûrˈbēəm [key] [from Ytterby, a village in Sweden], metallic chemical element; symbol Tb; at. no. 65; at. wt. 158.92535; m.p. 1,356℃; b.p. 3,123℃; sp. gr. about 8.25; valence +3 or +4....

aluminum

(Encyclopedia)aluminum ălˌyo͞omĭnˈēəm [key], metallic chemical element; symbol Al; at. no. 13; at. wt. 26.98154; m.p. 660.37℃; b.p. 2,467℃; sp. gr. 2.6989 at 20℃; valence +3. Aluminum is a silver-white...

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...

deuterium

(Encyclopedia)deuterium do͞otērˈēəm [key], isotope of hydrogen with mass no. 2. The deuterium nucleus, called a deuteron, contains one proton and one neutron. Deuterium is also called heavy hydrogen, and water...

faience

(Encyclopedia)faience fāĕnsˈ, –änsˈ, fī– [key] [for Faenza, Italy], any of several kinds of pottery, especially earthenware made of coarse clay and covered with an opaque tin-oxide glaze. The term is part...

carnelian

(Encyclopedia)carnelian kôr–, kər– [key], variety of red chalcedony, used as a gem. It is distinguished from sard by the shade of red, carnelian being bright red and sard brownish. The red coloring is apparen...

hydrogen

(Encyclopedia)hydrogen hīˈdrəjən [key] [Gr.,=water forming], gaseous chemical element; symbol H; at. no. 1; interval in which at. wt. ranges 1.00784–1.00811; m.p. −259.14℃; b.p. −252.87℃; density 0.08...

magnesia, chemical compound

(Encyclopedia)magnesia, common name for the chemical compound magnesium oxide, MgO. It occurs as colorless, cubic crystals. It is refractory, melting at about 2,800℃. It is very slightly soluble in pure water but...

ilmenite

(Encyclopedia)ilmenite ĭlˈmĕnīt [key], black mineral, iron titanium oxide, FeTiO3, crystallizing in the hexagonal system. It is sometimes found as tabular hexagonal crystals but occurs more commonly as small gr...