A number of reactions can be used to generate common gases on a laboratory scale. For example, nitrogen can be produced from sodium metal and potassium nitrate as indicated by the balanced equation: 10Na(s) + 2KNO3(s) —> K2O(s) + 5Na2O(s) + N2(g). A common laboratory-scale reaction can also generate oxygen gas by heating potassium chlorate, as indicated by the balanced equation: 2KClO3(s) —> KCl(s) + 3O2(g). What mass of potassium nitrate is needed to generate 241.0 L of gas, composed of 125.0 L of N2 and 116.0 L of O2 at 0.920 atm and 285 K, using these two reactions?