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|Atomic Number:||56||Atomic Symbol:||Ba|
|Atomic Weight:||137.34||Electron Configuration:||2-8-18-18-8-2|
|Melting Point:||725oC||Boiling Point:||1140oC|
|Description:||Soft heavy silver colored metal.|
|Uses:||Used as a "getter" in vaccum tubes. Its sulfate is used in X-ray
History(Gr. barys, heavy) Baryta was distinguished from lime by Scheele
in 1774; the element was discovered by Sir Humphrey Davy in 1808.
OccurenceIt is found only in combination with other elements, chiefly
with sulfate and carbonate and is prepared by electrolysis of the chloride.
- Barium is a metallic element, soft, and when pure is silvery white like
lead; it belongs to the alkaline earth group, resembling calcium chemically.
- The metal oxidizes very easily and should be kept under petroleum or other
suitable oxygen-free liquids to exclude air.
- It is decomposed by water or alcohol.
CompoundsThe most important compounds are the peroxide, chloride,
sulfate, carbonate, nitrate, and chlorate.
- The metal is used as a "getter" in vacuum tubes.
- Lithopone, a pigment containing barium sulfate and zinc sulfide, has good
covering power, and does not darken in the presence of sulfides.
- The sulfate, as permanent white is also used in paint, in X-ray diagnostic
work, and in glassmaking.
- Barite is extensively used as a weighing agent in oilwell drilling fluids,
and is used in making rubber.
- The carbonate has been used as a rat poison, while the nitrate and chlorate
give colors in pyrotechny.
- The impure sulfide phosphoresces after exposure to the light.
- All barium compounds that are water or acid soluble are poisonous.
IsotopeNaturally occurring barium is a mixture of seven stable
isotopes. Twenty two other radioactive isotopes are known to exist.