The Chemists' Delta
Thermodynamic quantities such as ΔG and ΔS are intensive functions and derivatives that depend on instantaneous values of the partial molar forms of various thermodynamic properties of reactions and products; they are not simple finite differences.
Craig, Norman C. 1987. "The Chemists' Delta." Journal of Chemical Education 64(8): 668.
American Chemical Society
Journal of Chemical Education
Chemistry and Biochemistry