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indium

(Encyclopedia)indium ĭnˈdēəm [key], a metallic chemical element; symbol In; at. no. 49; at. wt. 114.818; m.p. 156.6℃; b.p. about 2,080℃; sp. gr. 7.31 at 20℃; valence +1, +2, or +3. Indium is a soft, malle...

nonmetal

(Encyclopedia)nonmetal, chemical element possessing certain properties by which it is distinguished from a metal. In general, this distinction is drawn on the basis that a nonmetal tends to accept electrons and for...

bismuth

(Encyclopedia)bismuth bĭzˈməth [key] [Ger. Weisse Masse=white mass], metallic chemical element; symbol Bi; at. no. 83; at. wt. 208.98040; m.p. 271.3℃; b.p. about 1,560℃; sp. gr. 9.75 at 20℃; valence +3 or ...

transmutation of elements

(Encyclopedia)transmutation of elements, conversion of one chemical element into another. The expression has both historical and contemporary significance. The transmutation of certain metals into gold by means of ...

berkelium

(Encyclopedia)berkelium bûrˈklēəm [key] [from Berkeley], artificially produced radioactive chemical element; symbol Bk; at. no. 97; mass no. of most stable isotope 247; m.p. about 1,050℃; b.p. about 2,590℃;...

Norilsk

(Encyclopedia)Norilsk nərēlskˈ [key], city (1989 pop. 175,000), Krasnoyarsk Territory, N Siberian Russia. The northernmost major city of Russia and the world's second largest city (after Murmansk) above the Arct...

dubnium

(Encyclopedia)dubnium do͞obˈnēəm [key], artificially produced radioactive chemical element; symbol Db; at. no. 105; mass number of most stable isotope 268; m.p., b.p., and sp. gr. unknown; valence +5. Situated ...

zirconium

(Encyclopedia)zirconium zərkōˈnēəm [key], metallic chemical element; symbol Zr; at. no. 40; at. wt. 91.224; m.p. about 1,852℃; b.p. 4,377℃; sp. gr. 6.5 at 20℃; valence +2, +3, or +4. Zirconium is a very ...

night blindness

(Encyclopedia)night blindness, inability to see normally in subdued light. It is usually a result of vitamin A deficiency. The rod cells, one of two light-sensitive areas of the retina of the eye, are impaired in t...

lanthanum

(Encyclopedia)lanthanum lănˈthənəm [key] [Gr.,=to lie hidden], metallic chemical element; symbol La; at. no. 57; at. wt. 138.90547; m.p. about 920℃; b.p. about 3,460℃; sp. gr. 6.19 at 25℃; valence +3. Lan...