Zusammenfassung
We study the conductance of dil. aq. solns. for a series of guandinium salts at 298.15 K. The exptl. molar conductivities were analyzed within the framework of the Quint-Viallard theory in combination with Debye-Hueckel activity coeffs. From this anal., we find no evidence for significant ion assocn. in aq. solns. of guanidinium chloride (GdmCl) and guanidinium thiocyanate (GdmSCN), and the ...
Zusammenfassung
We study the conductance of dil. aq. solns. for a series of guandinium salts at 298.15 K. The exptl. molar conductivities were analyzed within the framework of the Quint-Viallard theory in combination with Debye-Hueckel activity coeffs. From this anal., we find no evidence for significant ion assocn. in aq. solns. of guanidinium chloride (GdmCl) and guanidinium thiocyanate (GdmSCN), and the molar cond. of these electrolytes can be modeled assuming a complete dissocn. For the bivalent salts guanidinium sulfate (Gdm2SO4) and guanidinium carbonate (Gdm2CO3), the molar conductivities show small deviations from ideal (fully dissocd. electrolyte) behavior, which are related to weak ion assocn. in soln. Furthermore, for solns. of Gdm2CO3, the hydrolysis of the carbonate anion leads to distinctively increased molar conductivities at high dilns. The obsd. ion assocn. is rather weak for all studied electrolytes and cannot explain the different protein denaturing activities of the studied guanidinium salts, as has been proposed previously.