The correct relationship between free energy change in a reaction and the corresponding equilibrium constant K_{c} is

- ΔG° = RT ln K
_{c} - -ΔG = RT ln K
_{c} - -ΔG = RT ln K
_{c} - -ΔG° = RT ln K
_{c}

**Answer**

ΔG = ΔG° + 2.303 RT log K_{c}

At equilibrium, ΔG = 0

ΔG° = –2.303 RT log K_{c}

**The correct option is D.**