The following data are obtained for the decomposition of N2O5 at a certain temperature: 2N2O5(g) ↔ 4NO2(g) + O2(g) Time(s) 0 200 400 600 800 N2O5 (atm) 2.70 2.41 2.15 1.92 1.71 Find the rate constant kobs for this first-order decomposition reaction. (Enter in sec-1)