Question

In the case of a simple conversion reaction such as X!Y, which value of ΔG° is associated with a larger concentration of X than Y at equilibrium? (Hint: How is ΔG° related to K?)

(A) ΔG° = -5
(B) ΔG° = -1
(C) ΔG° = 0
(D) ΔG° = 1

Answer 1

For a larger concentration of reactant X than product Y at equilibrium, ΔG° should be positive, indicating that the equilibrium favors the reverse reaction, making the correct answer (D) ΔG° = 1.

Step-by-step explanation:

The question refers to the Gibbs free energy change (ΔG°) for a simple reaction X ⇒ Y and its relationship with the equilibrium constant (K). When ΔG° is negative, it indicates that the reaction is spontaneously moving in the forward direction, producing more products than reactants, which implies a K > 1. Conversely, a positive ΔG° suggests that the reaction is spontaneous in the reverse direction, favoring the formation of reactants, with a K < 1. Therefore, for a larger concentration of X (reactant) than Y (product) at equilibrium, ΔG° should be positive, meaning the system favors the reverse reaction. This corresponds to choice (D) ΔG° = 1.