Ferrous amido-sulphonate, Fe(SO₃.NH₂)₂

Ferrous amido-sulphonate, Fe(SO₃.NH₂)₂.(?)5H₂O, is obtained by dissolving iron wire in aqueous amido-sulphonic acid, and concentrating in vacuo. The crystals are bluish green in colour, deliquescent, and exceedingly soluble in water, from which they are not precipitated by alcohol, thereby differing from ferrous sulphate. The crystals appear to contain 5 molecules of combined water.