Here are the essential concepts you must grasp in order to answer the question correctly.
Gibbs Free Energy (∆G)
Gibbs Free Energy (∆G) is a thermodynamic potential that measures the maximum reversible work obtainable from a thermodynamic system at constant temperature and pressure. A negative ∆G indicates a spontaneous process, while a positive ∆G suggests non-spontaneity. When ∆G is zero, as in this case, the system is at equilibrium, meaning the forward and reverse reactions occur at the same rate.
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Equilibrium Constant (K)
The equilibrium constant (K) is a dimensionless value that expresses the ratio of the concentrations of products to reactants at equilibrium for a given reaction. If K > 1, products are favored; if K < 1, reactants are favored. At equilibrium, when ∆G = 0, K is equal to 1, indicating that the concentrations of reactants and products are equal.
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Relationship between ∆G and K
The relationship between Gibbs Free Energy (∆G) and the equilibrium constant (K) is described by the equation ∆G° = -RT ln(K), where R is the gas constant and T is the temperature in Kelvin. This equation shows that if ∆G° is zero, then ln(K) is also zero, leading to K = 1. This indicates that at equilibrium, the concentrations of reactants and products are equal, reflecting a balance in the reaction.
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