Standard free energy of a reaction is determined from the equilibrium constant TABLE 8.4 Relation between AG and K'eg (at 25C) Reaction:A+B=C+D AGO Under standard conditions(1M K'eg keal mol-1 kJ/mol-1 10-5 concentrations,then△G=△Go) 6.82 28.53 10-4 5.46 22.84 10-3 4.09 17.11 △G=△Go+RTln(C]D]/LA][B]) 10-2 2.73 11.42 10-1 1.36 5.69 Keq =[C][D]/[A][B] 1 0 0 10 -1.36 -5.69 102 -2.73 -11.42 At pH 7: 103 -4.09 -17.11 104 -5.46 -22.84 △Go‘=-2.3 RTlogK'eq 105 -6.82 -28.53Reaction: A + B = C + D Under standard conditions (1M concentrations, then ΔG = ΔG○) ΔG = ΔG○ + RTln([C][D]/[A][B]) Keq = [C][D]/[A][B] At pH 7: ΔG○‘ = -2.3RTlogK’eq Standard free energy of a reaction is determined from the equilibrium constant