When NO and NO2 are mixed, the following equilibria are readily obtained;
2NO2⇌N2O4 ,KP=6.8 atm−1 and NO+NO2⇌N2O3
In an experiment when NO and NO2 are mixed in the ratio of 1 : 2, the find total pressure was 5.05 atm and the partial pressure of N2O4 was 1.7 atm. Calculate the equilibrium partial pressure of NO in atmosphere.