alkali metals


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Related to alkali metals: Halogens

alkali metals,

metals found in Group 1 of the periodic tableperiodic 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 table entitled
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. 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 lithiumlithium
[Gr.,=stone], metallic chemical element; symbol Li; at. no. 3; interval in which at. wt. ranges 6.938–6.997; m.p. about 180.54°C;; b.p. about 1,342°C;; sp. gr. .534 at 20°C;; valence +1. Lithium is a soft, silver-white metal.
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, sodiumsodium,
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.
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, potassiumpotassium
, a metallic chemical element; symbol K [Lat. kalium=alkali]; at. no. 19; at. wt. 39.0983; m.p. 63.25°C;; b.p. 760°C;; sp. gr. .862 at 20°C;; valence +1.

Potassium is a soft, silver-white metal.
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, rubidiumrubidium
, metallic chemical element; symbol Rb; at. no. 37; at. wt. 85.4678; m.p. 38.89°C;; b.p. 686°C;; sp. gr. 1.53 at 20°C;; valence +1. Rubidium is a very soft silver-white metal.
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, cesiumcesium
[Lat.,=bluish gray], a metallic chemical element; symbol Cs; at. no. 55; at. wt. 132.90545; m.p. 28.4°C;; b.p. 669.3°C;; sp. gr. 1.873 at 20°C;; valence +1. Cesium is a ductile, soft-as-wax, silver-white metallic element. It is in Group 1 of the periodic table.
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, and franciumfrancium
[from France], radioactive chemical element; symbol Fr; at. no. 87; mass no. of most stable isotope 223; m.p. about 27°C; (estimated); b.p. 677°C; (estimated); sp. gr. unknown; valence +1.
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References in periodicals archive ?
However, studies on the alkali metal status of Indian soils are extremely scarce, except for reports such as the one by Mehta et al.
According to the companies, SiGNa's patent-pending alkali metal reagents allow scientists and researchers to "dramatically" improve efficiencies and results, "bypassing traditional dangerous steps in alkali metal reduction processes.
The behavior of alkali metals during the combustion process can be characterized by their solubility in the boiling water.
We were originally developing a consumer product that would have benefited from this type of reduction reaction, but then realized that the market is much larger for a user-friendly form of the alkali metals themselves.
Rodgers & Amunugama suggested that the calculations underestimate the binding energy in the cases of toluene and fluorobenzene, when effective core potentials (ECPs) are used for heavier alkali metals like [Rb.
Like all alkali metals, sodium has one free electron that can react with other elements.
The trends in reactivity of alkali metals toward water.
Safe to use in air, without the need for extreme temperatures and pressures, the alkali metals are stabilized in an easy to handle and store powder and will be available through Sigma-Aldrich.
Researchers have already found that high pressure can force alkali metals, such as potassium, rubidium, and cesium, into behaving more like transition metals, such as iron, cobalt, and nickel.
They consist of reagents for organic synthesis, including alkali metals, alcoholates used as strong bases and catalysts, borane chemicals used for selective reductions and hydroborations, and new boron products that support the rapidly growing chemistry technology known as Suzuki coupling.