Le Chatelier's principle
Le Chatelier's principle describes the stability of a system in thermodynamic equilibrium[1][2]:
- In response to small deviations away from equilibrium, the system will change in a manner that restores equilibrium.
This translates to conditions on the second derivatives of thermodynamic potentials such as entropy, Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle S(U,\ldots)} . For instance, the entropy is a concave function of its arguments such as internal energy. Thus, one has
- Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \frac{\partial^2 S}{\partial U^2} \geq0\ .}
Similarly, specific heats can be shown to be positive definite.
References[edit]
- ↑ H. L. Le Chatelier, "Sur un énoncé général des lois des équilibres chimiques", Comptes rendus 99 pp. 786-789 (1884)
- ↑ H. L. Le Chatelier, Annales des Mines 13 pp. 157- (1888)
Related reading
- Denis J. Evans, Debra J. Searles, and Emil Mittag "Fluctuation theorem for Hamiltonian Systems: Le Chatelier’s principle", Physical Review E 63 051105 (2001)
- Pouria Dasmeh, Debra J. Searles, Davood Ajloo, Denis J. Evans, and Stephen R. Williams "On violations of Le Chatelier's principle for a temperature change in small systems observed for short times", Journal of Chemical Physics 131 214503 (2009)