Nitrogen forms a surprising number of compounds with oxygen. A number of these, often given the collective symbol (for "nitrogen oxygens") are serious contributors to air pollution. They can often be interconverted, sometimes by reaction with oxygen or ozone () in the air. An atmospheric scientist decides to study the reaction between nitrogen trioxide and oxygen that produces nitrogen dioxide and ozone. She fills a stainless steel reaction chamber with of nitrogen trioxide gas and of oxygen gas and raises the temperature considerably. At equilibrium she measures the mole fraction of ozone to be . Calculate the pressure equilibrium constant for the equilibrium between nitrogen trioxide, oxygen, nitrogen dioxide and ozone at the final temperature of the mixture. Round your answer to significant digits.