SINGLE-ION ACTIVITIES BY A SOLID ION TRANSMITTER BRIDGE AND A REFERENCE ELECTRODE WITHOUT LIQUID-JUNCTION

It had been shown that it is possible to measure thermodynamic values of single-ion activity using a solid ion conductor to bridge a reference electrode and a test electrode, thus eliminating liquid junction potentials. This led to redefinition of activity of an ion and brought out into sharp focus the crucial role of the charge factor in determining the effective strength of an ion. In this paper, we have measured potentials, free from liquid junction, using chloride ion sensors and the solid-ion transmitter bridge for determining chloride ion activity in zinc chloride solutions, leading to confirmation of definition of activity of an ion already proposed.