Temperature Coefficient of Electrode Electric Tension and Activity Coefficients of Individual Ionic Species.

Abstract : The electrodes Pt-H2/H(+)Br(-) and Ag/AgBr/Br(-)K(+) were investigated for the true temperature coefficient of their electric tension. The measurement at 25C and 35C were extended over the concentration range from about 0.1m down to about 0.001. The potentiometric experimental values corrected for the moality and the H2-pressure (for the Pt-H2/H(+) electrode) fit very well linear plots as function of the molality, thus allowing the extrapolation at zero ionic strength to be made. The value of the true temperature coefficient for the Ag/AgBr/Br(-) electrode was obtained new in this research. The values of the activity coefficients of Cl(-) and H(+) ions in HCl were computed on the basis of the experimental results given previously and compared with the values calculated theoretically and with the values of the mean activity coefficients of HCl obtained experimentally. (Author)