The concentration of N2O5 was monitored over time as it decomposed. 2 N2O5 (g) → 4 NO2 (g) + O2 (g) At 300.0 s, the concentration of N2O5 was 2.50×10−2 M. At 800.0 s, the concentration of N2O5 had decreased to 1.55×10−2 M. Calculate the average rate of change of O2 over the time interval from t = 300.0 s to t = 800.0 s.