Barium Tellurite, BaTeO₃

Barium Tellurite, BaTeO₃, may be obtained as a voluminous white precipitate from dilute solutions of an alkali tellurite and barium chloride. It always contains an amount of the latter which varies with the proportions used. With excess of barium chloride the precipitate may have the composition 8BaTeO₃.5BaCl₂.4H₂O, and with equivalent quantities of the two salts, 20BaTeO₃.½BaCl₂.20H₂O.

It may also be prepared by fusing together tellurium oxide and barium carbonate. Carbon dioxide is driven off and a yellow liquid formed which gives a colourless crystalline mass on cooling.

By fusion at incipient red heat an acid salt may be obtained as a clear colourless glass. The same compound is also formed as a voluminous flocculent precipitate by the action of very dilute nitric acid on the neutral salt.