Final answer:
To calculate the equilibrium constant using Aleks data resource, balance the equation, derive the equilibrium expression, and use the ICE table method if needed. If given the standard free energy change, use the equation ΔG° = -RTlnK to find K.
Step-by-step explanation:
To calculate the equilibrium constant for a given reaction using Aleks data resource, we need to follow several steps:
- Balancing the chemical equation: Ensure that the reaction equation is balanced.
- Deriving the equilibrium constant expression: Write an expression based on the stoichiometry of the reaction, whether it be in terms of concentration or partial pressures.
- Using thermodynamic data to calculate K: If given the standard free energy change (ΔG°), the equilibrium constant (K) can be calculated using the equation ΔG° = -RTlnK, where R is the ideal gas constant (8.314 J/mol·K) and T is the temperature in Kelvin.
- Applying the ICE table: This method involves listing the Initial concentrations of reactants and products, the Change that occurs as they reach equilibrium, and the Equilibrium concentrations.
- Putting in values and calculating: Substitute the equilibrium concentrations into the derived equilibrium expression to solve for K.
If we have a standard free energy change (ΔG°) of 55.7 x 10³ J/mol, we can calculate the equilibrium constant (K) at 298.15 K, using the ideal gas constant (R).
ΔG° = -RTlnK
55.7 x 10³ J/mol = -(8.314 J/mol·K)(298.15 K)lnK
By solving the above equation, we calculate the value of K.