Free Enthalpy or Gibbs Potential or Gibbs Free Energy

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If the pressure in an isothermal system is kept constant, (3.7.2) may be written in the form d(U - TS + pV) = dG = 0 (3.7.6)

where G (= U - TS + pV) is called the 'Free enthalpy' or Gibbs potential, or Gibbs free energy.

As with free energy in an isothermal-isometric system, the Gibbs free energy in an isothermal-isobaric system tends to be at its minimum value at equilibrium, i.e.,

where the sign of equality refers to a reversible system.

The Gibbs equilibrium condition (3.7.7) has been widely applied to study heat or energy transfer processes in many physical and chemical problems. It has been found to be particularly useful in studying the problems of evaporation and condensation in the atmosphere (see, e.g., Appendix-5).

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Getting Started With Solar

Getting Started With Solar

Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.

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