Thermodynamics of Chemical Equilibrium: Free Energy, Enthalpy and Entropy
Mar. 6, 2009
This web site covers the Gibbs Free energy equation. It goes into depth on both Enthalpy and Entropy. It also discusses how/why temperature has an effect on the free energy.
There is a table at the begining of the site that helps you to choose the part of Thermodynamics you would like to explore.