SPECIFIC COADSORPTION OF 2 IONS FROM MIXED-SOLUTIONS OF CONSTANT IONIC-STRENGTH IN THE FRAMEWORK OF THE GRAHAME-PARSONS MODEL

Specific co-adsorption of two ions from mixed electrolyte solutions of a constant ionic strength is analyzed in the framework of the Grahame -Parsons model. The model is shown to be consistent with the principal electrocapillarity equation for the systems studied. Specific co-adso rption of discharging cations and anions is considered. The two-humped electrocapillary curves, which qualitatively reflect the dependences observed experimentally at the interface between Hg and H2O + mc TlNO3 + (1 - m)c KNO3, are calculated theoretically. It is shown that speci fic adsorption of the reference ion may give rise to maximums in the c oncentration dependences of the interfacial tension.