Ionic Properties A Summary

In Section 2.15, methods for obtaining the propaties of individual ions (their hydration numbers, heats, and entropies) have been considered. Starting with a general method—extrapolation to eliminate the effect of a partner on the value of the (easily obtainable) corresponding electrolyte property—two special cases were dealt with how one obtains the individual values of the heat of hydration of the proton and then its entropy. 

Values of the thermal properties of individual ions do not have the same status as thermodynamic properties (for these are assumption-free). For thermodynamic properties, only the accuracy of the experimental determination can be questioned. For example, in electrochemical cells, are they being opo ated in equilibrium as required Thus, determining the values of the properties of individual ions always involves some assumption—that it is appropriate to extrapolate according to a certain l/r law, for example—and therefore the values will always be open to improvement. Some of the newer values increasingly refer to nonaqueous solutions. 

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