When△Gr=0: 0=△Gr=△G°+RTnQ At this time, all species concentrations do not change with time any more, i.e., the system has reached equilibrium Therefore. K 0=△G°+ RTIn K △G RTIn K nK=-△G°/RTor:logK=-△G°/2.303RT 11
When ΔGT = 0: 0 = ΔGT = ΔGT° + RT ln Q At this time, all species’ concentrations do not change with ti i th t h h d ilib i time any more, i.e., the system has reached equilibrium. Therefore: Q = K 0 = ΔGT° + RT ln K ΔGT° = – RTln K 11 ln K = – ΔGT° / RT or: log K = – ΔGT° / 2.303RT
△G △G°+ RTIn Q △G RT In K rtIn Q Q<K. AG<0 Reactant side >Product side Q=K, aG =0 No net reaction(in equilibrium) Q>K.AG>0 Product side Reactant side Therefore aG determines the direction of reaction △G° determines the level of reaction
ΔGT = ΔGT T ° + RT ln Q ΔGT = – RT ln K + RT ln Q Q < K, ΔG < 0 Reactant side Æ Product side Q = K, ΔG = 0 No net reaction (in equilibrium) Q > K, ΔG > 0 Product side G > 0 Product side Æ Reactant side Reactant side Therefore: ΔG determines the direction of reaction; ΔG° determines the level of reaction 12 determines the level of reaction