Chemical and Electrochemical Potential
Chemical Potential
Defined as the increase in free energy of a system with the addition of dni mole of component i; temperature, pressure and number of moles of all other components being constant.
Since we are ulimately concerned with ions, at least two kinds of ions must be added. Since dG is a perfect differential
Chemical potential can be expressed in terms of standard potential;
Electrochemical Potential
Since an ionic species has a different chemical potential in different phases, as two adjacent phases come to equilibrium with respect to a given species which exists in both species, there is a transfer of charge between the phases until the difference in chemical potential of the charged species is balanced by the electrical energy of the species with charge zi in phase a with potential f.
Expressed interms of the standard chemical potential;
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