What is Gibbs energy?

1 Answer
Dec 28, 2016

#"Gibbs Free Energy"# is the single unequivocal criterion for the spontaneity of the chemical change.

Explanation:

#DeltaG^@=DeltaH^@ -TDeltaS^@#

The defining expression thus includes an enthalpy term, and an entropy term. If #DeltaG^@# is negative, then the reaction is spontaneous as written. It can be related to the equilibrium constant by the expression, #DeltaG^@=-RTlnK_"eq"#. Clearly, only negative values of #DeltaG^@# will give positive equilibrium constants.