Membrane Potentials II. The measurement of the e. m. f. of cells containing the cation-exchange membrane, cross-linked polymethacrylic acid

Abstract

Measurements of membrane potentials, ionic transport numbers, solvent transport numbers, membrane composition and mtra-membrane activity coefficients for the system, KOH (aq.)/polymethacrylate membrane/KOH (aq.) are presented and used to test the principal theories of membrane potential. In no case was the agreement between the observed and calculated e.m.f.'s of the appropriate membrane cell sufficient to justify the calculation of membrane potentials from first principles. Possible reasons for these discrepancies are given.