Thermodynamic Theory of Electrochemical Systems

In this chapter we consider heterogeneous systems that consist of electrically conducting, homogeneous parts between which ionic components can be transferred. A representative example is the galvanic cell. 

The restraint of local electroneutrality has been removed from the systems of interest in this chapter. The magnitude of the composition fluctuations resulting from deviations from electroneutrality can be determined by a simple computation. Consider a spherical volume of radius 1 cm in a conducting medium. The electrostatic potential (p at the surface of this sphere is given by 

One mole of univalent, positive ions has a charge of . F =9.65 x 10 coulombs = 1 faraday. If, then, there is an excess of n moles of univalent, positive ions present in and on the sphere, the potential at the surface has the value 

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In this section, we derive a necessary condition for equilibrium in homogeneous conducting systems. Then, we develop the thermodynamic theory of electrochemical systems. 

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