In this communication, the correlation of some thermodynamic properties of structurally similar biological compounds with items such as the number of carbon atoms or the number of its characteristic groups, such as phosphates, was applied to enzyme thermodynamics, to advance the thermodynamics of fatty acid degradation. It was shown that these concepts apply equally well for all three major thermodynamic functions: Gibbs energy of formation, enthalpy of formation, and entropy of formation. First, the standard transformed Gibbs energies of formation, Delta(f)G'(o), were calculated for the major portion of saturated fatty acids at 25 degrees C and pH 5, pH 7, and 9. Second, a total ATP yield was calculated for complete combustion of major saturated fatty acids to CO2 and water. Third, the standard transformed Gibbs energies of reaction, Delta(r)G'(o), were calculated for enzyme reactions catalyzing complete beta-oxidation of butyryl-CoA to acetyl-CoA at 25 degrees C and pH 7.