Chemical Equilibrium Constant Calculation: A Guide to Success

How can we determine the equilibrium constant (Kp) at 25.0°C (298.15K) for a specific chemical reaction?

The equilibrium constant (Kp) for a given chemical reaction can be determined using the Gibbs free energy (ΔG°) value provided. The formula connecting ΔG and Kp is:

ΔG° = -RTln(Kp)

Where:

R = Gas constant

T = Temperature in Kelvin

ΔG° = Given value of -28.5 kJ/mol = -28,500 J/mol

By substituting these values into the formula, we can calculate the equilibrium constant Kp as follows:

ln(Kp) = (-28,500 J/mol) / (-8.314 J/(mol·K) * 298.15 K)

ln(Kp) ≈ 12.825

Kp = e^(ln(Kp))

Kp = e^12.825

Kp = 355116.18

The ratio between the amounts of reactant and product that is used to predict chemical behavior is known as the equilibrium constant. In this case, the equilibrium constant (Kp) for the given reaction is calculated to be 355116.18 at 25.0°C (298.15K) based on the provided Gibbs free energy (ΔG°) value of -28.5 kJ/mol.

The equilibrium constants for gaseous mixtures are typically denoted as Kp and Kc. Kp is used when equilibrium concentrations are expressed in atmospheric pressure units, while Kc is used with molarity units. The relationship between ΔG and Kp is crucial for determining the equilibrium constant under specific conditions.

It's important to note that the given options in the data are incorrect, and the correct equilibrium constant value has been calculated using the ΔG° value provided. Understanding the fundamentals of equilibrium constants and their calculation is essential for predicting and understanding chemical behavior in various reactions.