The use of enthalpy instead of internal energy in the definition of this quantity differentiates it from a related quantity central to the canonical ensemble.
The Margules activity model gives an expression for an excess in this quantity. The use of enthalpy instead of internal energy in the definition of this quantity differentiates it from a related quantity central to the canonical ensemble. For an electrochemical cell, this quantity is equal to the negative number of electrons times Faraday's constant times the electrode potential. The sign of this quantity determines whether a reaction is exergonic or endergonic. It equals zero at equilibrium, and it equals enthalpy minus entropy times temperature. For 10 points, name this thermodynamic quantity which is negative for a spontaneous reaction, symbolized by the letter G.
The Margules activity model gives an expression for an excess in this quantity.
Gibbs free energy [prompt on "free energy" or "G" before mention]