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
Barium hydroxide is mixed with many solutions of other metal salts. Reactions of barium hydroxide with ammonium salts are strongly endothermic. The reaction of barium hydroxide octahydrate with ammonium chloride or ammonium thiocyanate is often used as a classroom chemistry demonstration, producing temperatures cold enough to freeze water and enough water to dissolve the resulting mixture. Barium hydroxide presents the same hazards as other strong bases and as other water-soluble barium compounds: it is corrosive and toxic. Barium hydroxide Barium hydroxide is a chemical compound with the chemical formula Ba(OH)(HO). The monohydrate (x =1), known as baryta or baryta-water, is one of