At a particular temperature the first-order gas-phase reaction N2O5 -----> 2NO2 + (1/2)O2 has a half-life for the disappearance of dinitrogen pentoxide of 5130 s. Suppose 0.450 atm of N2O5 is introducted into an evacuated 2.00 L flask. What will be the total gas pressure inside the flask after 3.00 hours