What is K if #DeltaG^@# = -18.0 kJ for a reaction at 25 degrees C? Chemistry Thermochemistry Gibbs Free Energy 1 Answer Michael Apr 16, 2017 #sf(K=6.97xx10^(-4))# Explanation: #sf(DeltaG^@=-RTlnK)# #:.##sf(lnK=-(DeltaG^@)/(RT))# #sf(lnK=-(18xx10^3)/(8.31xx298)=-7.268)# #sf(K=6.97xx10^(-4))# Answer link Related questions Can gibbs free energy be negative? How do enzymes affect gibbs free energy? How is Gibbs Free Energy calculated? How is gibbs free energy related to enthalpy and entropy? Why does gibbs free energy decrease with temperature? Why is Gibbs free energy important? Why does Gibbs free energy have to be negative? Is Gibbs free energy affected by a catalyst? How can I calculate Gibbs free energy at different temperatures? How is Gibbs free energy measured? See all questions in Gibbs Free Energy Impact of this question 5496 views around the world You can reuse this answer Creative Commons License