About the Element
Barium (Greek "barys" meaning "heavy") was first identified in 1774 by Carl Scheele and extracted in 1808 by Sir Humphry Davy in England. Barium is a metallic element, soft, and when pure is silvery white; it belongs to the alkaline earth group, chemically resembling calcium. 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.
It is found only in combination with other elements, chiefly with sulfate and carbonate and is prepared by electrolysis of the chloride.
The metal is used as a "getter" in vacuum tubes. The sulfate is also used in paint, in X-ray diagnostic work, and in glassmaking. Barite is extensively used as a weighing agent in oil well 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 pyrotechnics. The impure sulfide phosphoresces after exposure to the light. All barium compounds that are water or acid soluble are poisonous. Naturally occurring barium is a mixture of seven stable isotopes. Twenty two other radioactive isotopes are known to exist.
About the Print
About the Printmaker
by Brad Robinson
Atomic number: 56
Atomic weight: 137.327