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rubidium

(Encyclopedia)rubidium ro͞obĭdˈēəm [key], metallic chemical element; symbol Rb; at. no. 37; at. wt. 85.4678; m.p. 38.89℃; b.p. 686℃; sp. gr. 1.53 at 20℃; valence +1. Rubidium is a very soft silver-white ...

Rb

(Encyclopedia)Rb, symbol for the element rubidium. ...

alkali metals

(Encyclopedia)alkali metals, metals found in Group 1 of the periodic table. Compared to other metals they are soft and have low melting points and densities. Alkali metals are powerful reducing agents and form univ...

Kirchhoff, Gustav Robert

(Encyclopedia)Kirchhoff, Gustav Robert go͝osˈtäf rōˈbĕrt kĭrkhˈhôf [key], 1824–87, German physicist. He served as professor of physics at the universities of Breslau (1850–54), Heidelberg (1854–74), ...

flame test

(Encyclopedia)flame test, test used in the identification of certain metals. It is based on the observation that light emitted by any element gives a unique spectrum when passed through a spectroscope. When a salt ...

Cornell, Eric Allin

(Encyclopedia)Cornell, Eric Allin, 1961–, American physicist, b. Palo Alto, Calif., Ph.D. Massachusetts Institute of Technology, 1990. Since 1990, he has been a researcher at the Joint Institute for Laboratory As...

Wieman, Carl Edwin

(Encyclopedia)Wieman, Carl Edwin, 1951–, American physicist, b. Corvallis, Oreg., Ph.D. Stanford, 1977. He was a professor at the Univ. of Colorado from 1984 to 2006. In 2007, he joined the Univ. of British Colum...

Bunsen, Robert Wilhelm

(Encyclopedia)Bunsen, Robert Wilhelm bŭnˈsən, Ger. rōˈbĕrt vĭlˈhĕlm bo͝onˈzən [key], 1811–99, German scientist, educated at the Univ. of Göttingen, where he received his doctorate in 1830. He served ...

gallium

(Encyclopedia)gallium gălˈēəm [key], metallic chemical element; symbol Ga; at. no. 31; at. wt. 69.723; m.p. 29.78℃; b.p. 2,403℃; sp. gr. 5.904 at 29.6℃ (solid), 6.095 at 29.8℃ (liquid); valence +2 or +3...

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