Barium green color. Barium sulfate is used as an insoluble additive to oil well drilling fluid, as well as in a purer form, as X-ray radiocontrast agents for imaging the human gastrointestinal tract. The soluble barium ion and soluble compounds are poisonous, and have been used as rodenticides. Barium is a soft, silvery-white metal, with a slight golden shade when ultrapure. The silvery-white color of barium metal rapidly vanishes upon oxidation in air yielding a dark gray oxide layer. Barium has a medium specific weight and good electrical conductivity. Ultrapure barium is very difficult to prepare, and therefore many properties of
Calcium chlorate complicated by calcium hydroxide depositing on the cathode, preventing the flow of current. When concentrated solutions of calcium chlorate and potassium chloride are combined, potassium chlorate precipitates: This is the second step of the Liebig process for the manufacture of potassium chlorate. Solutions of calcium chlorate react with solutions of alkali carbonates to give a precipitate of calcium carbonate and the alkali chlorate in solution: On strong heating, calcium chlorate decomposes to give oxygen and calcium chloride: Cold, dilute solutions of calcium chlorate and sulfuric acid react to give a precipitate of calcium sulfate and chloric acid in solution: Contact