| 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 |