The dinitrogen Peroxide decomposes into the two gas phase first, nitrogen dioxide and second, oxygen gas. The reaction is first order indinitrogen Peroxide and has a half-life of 2.81 h at 25 degrees Celsius. At 25 degrees Celsius if a 1.5-L reaction vessel initially has 745torr of N2O5, explain what partial pressure of O2 will be present in the vessel after 215 minutes?