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 indicates the spontaneity of a reaction at constant temperature and pressure. A negative ∆G° value, such as -1.8 kcal/mol, suggests that the reaction is spontaneous in the forward direction, favoring the formation of products. Understanding this concept is crucial for predicting the direction of equilibrium and the extent to which reactants are converted to products.
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Breaking down the different terms of the Gibbs Free Energy equation.
Equilibrium Constant (K<sub>eq</sub>)
The equilibrium constant (K<sub>eq</sub>) quantifies the ratio of the concentrations of products to reactants at equilibrium for a reversible reaction. It is calculated using the formula K<sub>eq</sub> = [products]/[reactants]. A K<sub>eq</sub> greater than 1 indicates that products are favored at equilibrium, while a value less than 1 suggests that reactants are favored. This concept is essential for determining the composition of the equilibrium mixture.
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Percent Composition at Equilibrium
Percent composition at equilibrium refers to the distribution of reactants and products in a chemical reaction once it has reached equilibrium. It is calculated by determining the mole fractions of each component and converting these to percentages. This concept is important for understanding how much of each species is present in the mixture at equilibrium, which can be derived from the K<sub>eq</sub> value and the initial concentrations of reactants.
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