Crystal hydrates of Mn(CHSO)·2HO, Co(CHSO)·4HO and Ni(CHSO)·4HO were synthesized and identified by X-ray phase analysis, inductively coupled plasma atomic emission spectroscopy and thermogravimetry. The enthalpies of dissolution in water at 298.15 K were determined by dissolution calorimetry and the standard enthalpies of formation of crystalline hydrates of manganese, cobalt and nickel methanesulfonates were calculated. The enthalpic contribution of the methanesulfonate ion to the enthalpy of crystalline methanesulfonate formation in an additive scheme was estimated from the data obtained.
E. V. Belova (Wed,) studied this question.