AN INVESTIGATION OF THE HYDRATES OF CALCIUM SULPHITE

Abstract

Numerous references are found to the dihydrate of calcium sulphite, first reported by Muspratt in 1844. Repetition of this work showed no evidence of the formation of a dihydrate at room temperature but rather a hemihydrate. The optical properties reported for the dihydrate were those of the hemihydrate. The X-ray diffraction powder data reported for the anhydrous salt were found to check those of the hemihydrate. The hemihydrate was found to be stable to heating at 250 °C. The dehydration to the anhydrous salt was accomplished by heating in a vacuum at 300 °C.