The formula to calculate the equilibrium constant is:
\[ K = \frac{[C]^c [D]^d}{[B]^b [A]^a} \]
Where:
An equilibrium constant is a constant used to describe when a solution will be at equilibrium. It is a measure of the relative concentrations of reactants and products in a chemical reaction at equilibrium.
Example:
Using the formula:
\[ K = \frac{[1.0]^1 [1.0]^1}{[0.5]^1 [0.5]^1} = 4 \]
The equilibrium constant (K) is 4.