Write A Short Note On Gibbs Free Energy And Derive The Equation For The Same.?
This thermodynamic quantity states that the decrease in value during a process is equal to the useful work done by the system. It is denoted by G and the mathematical equation is: G = H – TS Where, H = heat content T = absolute temperature S = entropy of the system For isothermal process we have G1 = H1 – TS1 for the initial state G2 = H2 – TS2 for final stage Therefore, G2 – G1 = (H2 – H1) – T(S2 – S1) Now, ΔG = G2 – G1 is the change in Gibbs free energy ΔH = H2 – H1 is the change in enthalpy of the system ΔS = S2 – S1 Is the change in entropy of the system Thus the above equation becomes: ΔG = ΔH – TΔS is known as Gibbs-Helmoholtz equation.
