Thermodynamics of Continua

The extension of the fundamental equations of Thermodynamics to a description of macroscopic systems in terms of continuous state variables is developed. All the basic relations as mass conservation in the presence of chemical reactions, the equation of motion and the equations for energy and that for entropy which express, in the new formalism, the First and the Second Principles, respectively, must be reformulated. The correct expression for the entropy production and the consequent expressions for the fluxes and the corresponding generalized forces are obtained. In the linear regime, the general relation between the mobility of ionic species and the coefficient of diffusion (Einstein relation) is demonstrated. The thermoelectric phenomena (Seebeck, Peltier, and Thomson effects) are discussed together with the thermodiffusion processes. An appendix concerning the Gibbs–Duhem relation closes the Chapter.