Real Ion Activity

Rabinovich et al. have shown that it is possible to propose an extrather-modynamic definition of single-ion activity, a, as a function of the real potentials of those particles. By carrying out the measurements of voltaic cells containing electrodes reversible to the same ionic species in solutions of different concentrations in the same solvent. 

Therefore the real and chemical ionic activity coefficients are related by the formula  

If the concentration change in the surface potential, A % is close to zero (see Section XII), the real and chemical activities are the same. 

On the basis of this definition, one can determine, for instance, the activity of electrolytic solutions in terms of the real hydrogen ion activity. Rybkin et al. found that the Ax effect may be stabilized by adding surface-active substances in small quantities to the solution. Ac- 

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