What is Chemical potential: Definition and 96 Discussions

In thermodynamics, the chemical potential of a species is the energy that can be absorbed or released due to a change of the particle number of the given species, e.g. in a chemical reaction or phase transition. The chemical potential of a species in a mixture is defined as the rate of change of free energy of a thermodynamic system with respect to the change in the number of atoms or molecules of the species that are added to the system. Thus, it is the partial derivative of the free energy with respect to the amount of the species, all other species' concentrations in the mixture remaining constant. The molar chemical potential is also known as partial molar free energy. When both temperature and pressure are held constant, chemical potential is the partial molar Gibbs free energy. At chemical equilibrium or in phase equilibrium the total sum of the product of chemical potentials and stoichiometric coefficients is zero, as the free energy is at a minimum.In semiconductor physics, the chemical potential of a system of electrons at zero absolute temperature is known as the Fermi energy.

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  1. E

    I How to see this form for the chemical potential of an ideal gas?

    In Chapter 13.2 of his text, Callen states that the chemical potential with respect to the ##j##th component of an ideal gas can be written as $$\mu_j = RT \left[\phi_j(T) + \ln P + \ln x_j \right].$$ He states this outright and doesn't prove it, and I am trying to do so now. Based on what has...
  2. Dario56

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  3. G

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  4. chikchok

    I Chemical potential and Fermi level

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  5. B

    Calculating particle numbers in diffusive equilibrium of a battery

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  6. Kaguro

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  7. J

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  8. E

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  9. QuarkDecay

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  13. L

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  15. P

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  16. amjad-sh

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  17. Pushoam

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  18. F

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  19. V

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  20. W

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  21. M

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  22. RicardoMP

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  23. D

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  24. H

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  30. Coffee_

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  31. C

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  33. A

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  34. T

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  36. ChristineMarie

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  37. D

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  38. B

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  39. C

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  40. alpha358

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  41. A

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  42. D

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  43. Useful nucleus

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  44. A

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  45. A

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  46. A

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  47. T

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  48. I

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  49. G

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  50. U

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