Question

The correct relationship between free energy change in a reaction and the corresponding equilibrium constant Kc is
(a) – $\Delta G$ = RT ln $K_c$
(b) $\Delta G^0$ = RT ln $K_c$
(c) – $\Delta G^0$ = RT ln $K_c$
(d) $\Delta G$ = RT ln $K_c$

Answer 1

Given: The relation between free energy change and equilibrium constant

To find: Relationship between free energy change and corresponding equilibrium constant in a given reaction

Explanation: The relationship between Combining terms gives the following relationship between ΔG and the reaction quotient Q:

ΔG=ΔG$+RTlnK_{C}$

where ΔG° indicates that all reactants and products are in their standard states. For a system at equilibrium ( K=Q ,), and as you’ve learned in this chapter, ΔG = 0 for a system at equilibrium. Therefore, we can describe the relationship between ΔG° and K as follows:

Δ$G=-RTlnK_{C}$

Hence the correct answer is option A