The equilibrium constant Kc for a chemical reaction is the ratio of the concentrations of the products to the concentrations of the reactants, each raised to the power of their stoichiometric coefficients in the balanced chemical equation. For the given reaction:2NO2 g N2O4 g The equilibrium constant expression is:Kc = [N2O4] / [NO2]^2At 25C, the Kc value for this reaction is approximately 4.63 x 10^4. This value can be found in various chemistry reference sources, such as textbooks or online databases.The interpretation of this Kc value is that at equilibrium, the concentration of N2O4 is much higher than the concentration of NO2. A large Kc value indicates that the reaction favors the formation of products N2O4 in this case over the reactants NO2 . In other words, at 25C, the reaction strongly favors the dimerization of NO2 to form N2O4.