Question

At equilibrium, the concentrations of reactants and products can be predicted using the equilibrium constant, Kc , which is a mathematical expression based on the chemical equation. For example, in the reaction aA+bB⇌cC+dD where a , b , c , and d are the stoichiometric coefficients, the equilibrium constant is Kc=[C]c[D]d[A]a[B]b where [A] , [B] , [C] , and [D] are the equilibrium concentrations. If the reaction is not at equilibrium, the quantity can still be calculated, but it is called the reaction quotient, Qc , instead of the equilibrium constant, Kc . Qc=[C]tc[D]td[A]ta[B]tb where each concentration is measured at some arbitrary time t .

Part A Part complete A mixture initially contains A , B , and C in the following concentrations: [A] = 0.450 M , [B] = 0.850 M , and [C] = 0.300 M . The following reaction occurs and equilibrium is established: A+2B⇌C At equilibrium, [A] = 0.300 M and [C] = 0.450 M . Calculate the value of the equilibrium constant, Kc .