The pure metal is used as a “getter” in vacuum tubes andisintroduced to lead bearing metals via electrolysis to hardenthelead. However the most extensive use of barium is in the form ofitscompounds of which the most important are theperoxide(BaO2), chloride (BaCl2),sulphate(BaSO4), carbonate (BaCO3),nitrate(Ba(NO3)2),chlorate(Ba(ClO3)2.H2O), andhydride(BaH2). · Thesulphate is used in pigments and glassmaking, and theinsolublenon-toxic form is used in radiography. · Thecarbonate is used as a rat poison. · Thenitrate and chlorate produce colours in pyrotechnics. · Impuresulphide phosphoresces upon exposure to light. · Bariumheat-treated to 200°C (392°F) in a hydrogen gas it formsbariumhydride (BaH2), a grey powder that decomposes oncontactwith water and can be used as a source of nascent hydrogenfor liferafts. · Bariums also a key element in the production ofceramic superconductors. |