TELLURIC ACID

Properties

Safety Information

Description

Telluric acid, H6TeO6, is obtained in the form of its salts when tellurium is fused with potassium nitrate plus carbonate, or by the oxidizing action of chlorine on a tellurite in alkaline solution. The free acid may be obtained by decomposing the barium salt with sulfuric acid and concentrating the solution.
where tellurium is in an octahedral coordination. Telluric acid, Te(OH)6, has the CAS number of 7803-68- 1 and a molecular weight of 229.6425 g/mol. It is a white, monoclinic crystal with a density of 3.07 g/cm³. Its melting point is 136°C and its solubility in water is 50.1 g/100 ml.
It is also formed when tellurium dioxide is oxidized by hydrogen peroxide in caustic solution (A. Gutbier, Zest. Anorg. Chem., 1904, 40, p. 260), and perhaps best of all by oxidizing tellurium with a mixture of nitric and chromic acids. It crystallizes as prisms, which lose their water of hydration at 160°C. The tellurates of the alkaline earth metals are more or less soluble in water, those of the other metals being very sparingly or almost insoluble in water. Some tellurates exist in two forms, a colorless form soluble in water and acids, and a yellow form insoluble in water and acids.