The equilibrium constant expression for a reaction is given by the ratio of the concentrations of the products raised to their stoichiometric coefficients divided by the concentrations of the reactants raised to their stoichiometric coefficients.For the given reaction:H2 g + I2 g 2HI g The equilibrium constant expression Kc can be written as:Kc = [HI]^2 / [H2] * [I2] Where [HI], [H2], and [I2] represent the equilibrium concentrations of HI, H2, and I2, respectively.