Consider this rxn which has a Δ G ° = +0.4 kJ\mol.
A + B ↔ C + D
1 M A, 1 M B, 0.1 M C and 0.1 M D are added to a container at room temperature. Which of the following statements is true?
A) Δ G
B) Δ G = 0
C) Δ G 0 (i.e., it's positive)
D) Cannot be determined from the information provided.

Question

Consider this rxn which has a Δ G ° = +0.4 kJ\mol.
A + B ↔ C + D
1 M A, 1 M B, 0.1 M C and 0.1 M D are added to a container at room temperature. Which of the following statements is true?
A) Δ G
B) Δ G = 0
C) Δ G > 0 (i.e., it's positive)
D) Cannot be determined from the information provided.

Quizplus · Accepted Answer

The reaction quotient Q = [C][D]/[A][B] = (0.1)(0.1)/(1)(1) = 0.01. Since ΔG° = +0.4 kJ/mol, the reaction is not at equilibrium. ΔG = ΔG° + RTlnQ. Given Q < 1, lnQ < 0, making ΔG < ΔG°. Since ΔG° is positive, ΔG is still positive but less than ΔG°.

Consider This Rxn Which Has a Δ G ° =