A mixture initially contains A, B, and C in the following concentrations: [A] = 0.300M, [B]= 0.650M , and [C] = 0.600M . The following reaction occurs and equilibrium is established:
A + 2B <----> C
At equilibrium, [A] = 0.120M and [C] = 0.780M . Calculate the value of the equilibrium constant, Kc.