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Thermodynamics of formation of double salts and mixed crystals from aqueous solutions

“…For most of the systems investigated, the model predicted solubilities in ternary mixtures agree very well with the experimental data obtained by us [27][28][29]33,[36][37][38]54,58,61,62] and those given in the literature . Additional experiments were performed [27][28][29]31,41,44] to check contradictory data reported in the literature and specify the type of the solubility diagrams.…”

“…For chloride and bromide systems [27,28,34] containing the same cations (M + and M 02+ ), where double salts with the same stoichiometric composition crystallize, the following relationships have been found: (i) the absolute value of the sum of the ternary parameters for the bromide systems is larger than that for the corresponding chloride system and (ii) the D r G m values for the chloride double salts are lower than those for the corresponding bromide double salts. Proceeding from the foregoing and taking into account the condition about thermodynamic stability of double salts (a negative D r G m value), we have constructed a preliminary mixing solution model, and plotted preliminary theoretical solubility isotherms for the (m 1 RbBr + m 2 NiBr 2 )(aq) [38] and (m 1 RbBr + m 2 MnBr 2 )(aq) [39] systems. The experiments have confirmed the results of the calculation.…”

Study of (m1LiX+m2CaX2)(aq) wheremidenotes molality andXdenotes Cl, or Br at the temperature 298.15 K

“…(5,(17)(18)(19) In calculating the ternary parameters we have included the unsymmetrical mixing terms E θ and E θ , according to reference 14. In our previous studies on chloride and bromide systems (5,6,15,(24)(25)(26)(27) containing the same cations (M + and Me 2+ ), and where double salts with the same stoichiometric composition crystallize, the following relationships have been found: the absolute value of the sum of the ternary parameters for the bromide systems is larger than that for the corresponding chloride system, and the r G o m values for the chloride double salts are lower than those for the corresponding bromide double salts. Using the foregoing model The solubility isotherms of the ternary solutions at T = 298.15 K are calculated on the basis of the thermodynamic functions obtained.…”

Ternary Diagram of RbX–MnX2–H2O (X = Cl, Br) at T = 298.15 K and the Standard Enthalpies of Dissolution and Formation of Their Double Salts

“…Solubility graph of MnBr 2 and RbBr in water at 298.15 K. E 3 and E 4 stand for the double-saturation points. The blue line represents data from ref , and the black line represents data from this work.…”

“…Balarew et al simulated thermodynamically the RbBr–MnBr 2 –H 2 O system with the Pitzer ion-interaction model. Solubility diagrams of RbBr, Rb 2 MnBr 4 ·2H 2 O, and MnBr 2 ·4H 2 O at 298.15 K were assumed and plotted . Balarew and Tepavitcharova tried to discover the regularities concerning the formation of double salts in the systems of the MX–MeX 2 –H 2 O type, where M + = K + , NH 4 + , Rb + , Cs + , Me 2+ = Mg 2+ , Mn 2+ , Fe 2+ , Co 2+ , Ni 2+ , Cu 2+ , and X – = Cl – , Br – .…”