Alkaline-Earth Metal


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Alkaline-Earth Metal

 

any one of the chemical elements of the main subgroup of Group II of Mendeleev’s periodic system, comprising the calcium family: calcium, strontium, barium, and radium (beryllium and magnesium are also sometimes considered to be alkaline-earth metals). The origin of the name is related to the fact that the oxides of the alkaline-earth metals (”eerths” in alchemical terminology) were found to be alkaline in water. The outer electron shell of alkaline-earth metal atoms contains two 5 electrons; the preceding shell contains two s and six p electrons. The alkaline-earth metals exhibit an oxidation number of +2 in their compounds. They are chemically reactive, and their reactivity increases from calcium to radium. (See alsoCALCIUM; STRONTIUM; BARIUM; and RADIUM.)

References in periodicals archive ?
Contributors from Europe and South Africa provide background on ferroalloy basics, thermodynamics, the kinetics of reduction and general processing issues, electric furnace operations, environmental issues, and other general topics, followed by the theory and technology of ferroalloys with silicon, manganese, high carbon, and chromium, and minor ferroalloys like ferronickel, tungsten, molybdenum, vanadium, niobium, titanium, zirconium, boron, and rare-earth and alkaline-earth metals.
Oxide cathodes of that time represented a mixture of oxides of such alkaline-earth metals as calcium, strontium and barium.
2], and the best emission additives are oxides of alkaline-earth metals.