Barium Thioarsenites

A number of thioarsenites can be obtained by the action of barium hydrosulphide on arsenic trisulphide under different conditions. The following may be mentioned: - BaS.As₂S₃.2H₂O, BaS.6As₂S₃, 2BaS.As₂S₃.2H₂O, in two forms, one grey-green and the other indigo-blue, 2BaS.As₂S₃, 2BaS.As₂S₃.15H₂O, Ba₃(AsS₃)₂ a white crystalline compound insoluble in alcohol, Ba₃(AsS₃)₂.14H₂O, and the pyrothioarsenite, Ba₂As₂S₅, forming a brown- red gummy substance very soluble in water. There is also a thio-oxyarsenite, 5BaS.2As₂S₂O.6H₂O