standard free energies of formation, Gfo -- are tabulated for pure solids, pure liquids, gases at ~1 atm pressure, and 1 M solutions -- For elements in their standard states… -- For a reaction, the standard free-energy change is found by… EX. Calculate the standard free-energy change for… PCl3(g) + Cl2(g) PCl5(g) Free Energy and Temperature From = TS, we see that varies with temperature. G H G – -- -- and change little with temperature. H S EX. (a) Calculate and for… 2 NO(g) + O2(g) 2 NO2(g) Ho, Go, So (b) Estimate at 400 K. G
standard free energies of formation, Gfo -- are tabulated for pure solids, pure liquids, gases at ~1 atm pressure, and 1 M solutions -- For elements in their standard states… -- For a reaction, the standard free-energy change is found by… EX. Calculate the standard free-energy change for… PCl3(g) + Cl2(g) PCl5(g) Free Energy and Temperature From G = H – TS, we see that G varies with temperature. -- -- H and S change little with temperature. EX. (a) Calculate Ho, Go, and So for… 2 NO(g) + O2(g) 2 NO2(g) (b) Estimate G at 400 K.
19_thermodyn_stunotes_s12.docx