At a certain temperature, a 29.5-L contains holds four gases in equilibrium. Their masses are: 3.5 g SO3, 4.6 g SO2, 19.8 g N2, and 0.98 g N2O. What is the value of the equilibrium constant at this temperature for the reaction of SO2 with N2O to form SO3 and N2 (balanced with lowest whole-number coefficients)?