Ammonium iron(II) sulphate hexahydrate. Purification and storage
Abstract
This paper proposes a simple purification method for ammonium iron(II) sulphate hexahydrate (FAS) or Mohr's salt, which produces material of reliably 99.9% effective purity and ready for weighing in about 1 h. The preparation, assay and storage properties are described. Less detailed results are given for ethylenedi-ammonium iron(II) sulphate tetrahydrate, FeSO4.C2H4(NH3)2SO4.4H2O (Oesper's salt).