ADSORPTION OF N-TOSYLGLYCINE AT THE HG AQUEOUS-SOLUTION INTERFACE AT VARIOUS PH VALUES

The adsorption of N-tosylglycine (CH//3-O-SO//2-NH-CH//2COOH) has been studied at the mercury/aqueous solution interface (0. 1 M NaClO//4 as base electrolyte) with the aim of comparing the interfacial properties of the molecular forms of the amino acid present in solution at different pH values. The analysis of the interfacial behavior was performed by tensammetric measurementw using an ac phase selective polarographic method at pH equals 4, 6 and 12. It has been shown that the adsorption isotherm (Frumkin type) is congruent with respect to the potential, with a slight attractive interaction factor at pH equals 4, but higher and repulsive at pH equals 6 and 12. At pH equals 4 the species adsorbed seems to be the neutral one, while at pH equals 6 and 12 the monoanionic species seems to be involved in the electrode interaction.