Collection of Czechoslovak Chemical Communications - digital archive 

Abstract

Solubility isotherms of MgCl₂·6H₂O at 25 °C in solutions of chlorides of bivalent beryllium, calcium, manganese, iron, cobalt, zinc and mercury were treated by the hydration analysis. In addition to the usual procedure, the recently developed modified transfer energy Ξ was used to characterize the situation in saturated solutions. As a result, the following ionic processes were established in the saturated solutions under consideration: competition for water in solutions of MgCl₂·6H₂O containing beryllium and calcium chloride, complex formation in solutions of MgCl₂·6H₂O containing manganese, cobalt, zinc and mercury ions and formation of ions with heterogeneous coordination sphere in solutions of MgCl₂·6H₂O containing iron or copper ions. In the last case, the ability of the formed ions to crystallize from solution was found to be reduced in comparison with the other cases. Activity coefficients of MgCl₂ were calculated along the solubility curves under consideration.

Keywords: Solubility; Aqueous solutions; Hydration analysis; Activity coefficients; Magnesium chloride hexahydrate; Divalent metal chlorides; Crystallization.

References: 15 live references.