Final answer:
b) ΔG° + RT ln [X]/[Y] = 0. The correct answer is option (b) when [X]/[Y] represents the equilibrium concentrations and Q = K. The formula for a reaction at equilibrium is 0 = ΔG° + RTlnK.
Step-by-step explanation:
The question refers to the properties of a chemical reaction at equilibrium. Option (b) ΔG° + RT ln [X]/[Y] = 0 is correct if [X]/[Y] represents the reaction quotient Q at equilibrium, since in this case Q equals the equilibrium constant K. However, as written it is somewhat misleading because [X] and [Y] should represent the equilibrium concentrations, not just any concentrations, and it should be clarified that Q is equal to K when a reaction is at equilibrium. The correct answer is (b) if this understanding is applied. The relevant formula here is ΔG = ΔG° + RTlnQ, and at equilibrium, ΔG = 0 and Q = K, making the equation 0 = ΔG° + RTlnK.
Equilibrium constant (K), Gibbs free energy (ΔG), and the reaction quotient (Q) are critically important concepts in the study of chemical equilibrium. They help us understand whether a reaction will proceed spontaneously and in which direction it will tend to go before reaching equilibrium.
At equilibrium, the value of the equilibrium constant is equal to the reaction quotient for the reaction. This can be expressed as ΔG = ΔG° + RT ln Q, where ΔG is the Gibbs free energy change, ΔG° is the standard Gibbs free energy change, R is the ideal gas constant, T is the temperature in Kelvin, and Q is the reaction quotient. Since at equilibrium ΔG = 0, the correct statement among the given options is (c) RT ln [X]/[Y] = 0.