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alkali metals |
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alkali metals, metals found in Group 1 of the periodic table periodic table, chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley . In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the ..... Click the link for more information. . Compared to other metals they are soft and have low melting points and densities. Alkali metals are powerful reducing agents and form univalent compounds. All react violently with water, releasing hydrogen and forming hydroxides. They tarnish rapidly even in dry air. They are never found uncombined in nature. In order of increasing atomic number the alkali metals are lithium lithium (lĭth`ēəm) [Gr.,=stone], metallic chemical element; symbol Li; at. no. 3; at. wt. 6.941; m.p. about 180.54°C;; b.p. ..... Click the link for more information. , sodium sodium, a metallic chemical element; symbol Na [Lat. natrium]; at. no. 11; at. wt. 22.98977; m.p. 97.81°C;; b.p. 892.9°C;; sp. gr. 0.971 at 20°C;; valence +1. Sodium is a soft, silver-white metal. ..... Click the link for more information. , potassium potassium (pətăs`ēəm), a metallic chemical element; symbol K [Lat. kalium=alkali]; at. no. 19; at. wt. 39.0983; m.p. ..... Click the link for more information. , rubidium rubidium (r bĭd`ēəm), metallic chemical element; symbol Rb; at. no...... Click the link for more information. , cesium cesium (sē`zēəm) [Lat.,=bluish gray], a metallic chemical element; symbol Cs; at. no. 55; at. wt. 132.9054; m.p. 28.4°C;; b. ..... Click the link for more information. , and francium francium (frăn`sēəm) [from France], radioactive chemical element; symbol Fr; at. no. 87; mass no. ..... Click the link for more information. . How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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| ? Mentioned in | ? References in periodicals archive | ||
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| Meteoric waters in near-surface settings are almost always
undersaturated with respect to carbonates because rain water is
essentially devoid of earth alkali metals yet slightly acidic because of
dissolved atmospheric C[O. The new observation that sodium can melt at
just above room temperature, 27[degrees]C, confirms a growing suspicion
among scientists that alkali metals are more complicated than they
previously thought. This is especially
important in alkali metals where the one valence electron is
particularly sensitive to any core changes. |
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