Final answer:
When a reaction is non-spontaneous and reactants are favored, the value of ∎G is positive, the value of E°cell is negative, and the value of K is less than 1. This indicates that the reaction will not occur spontaneously in the forward direction under standard conditions. However, it may occur spontaneously in the reverse direction.
Step-by-step explanation:
When a reaction is non-spontaneous and reactants are favored, the value of ∎G is positive, the value of E°cell is negative, and the value of K is less than 1. This indicates that the reaction will not occur spontaneously in the forward direction under standard conditions. However, it may occur spontaneously in the reverse direction. If the reaction is forced to occur in the forward direction, an input of electrical energy is required.
For example, let's consider the reaction:
2 Ce+ (aq) + 2 Cl- (aq) → 2 Ce3+ (aq) + Cl2 (g)
E°cell for this reaction is 0.25 V, which is positive, indicating spontaneity. However, under nonstandard conditions, the value of Ce4+ = 0.013 M, Ce3+ = 0.60 M, Cl = 0.0030 M, PC12 = 1.0 atm, and T = 25°C. To calculate Ecell and determine spontaneity, the Nernst equation can be used.