The reaction 2NO2 → 2NO + O2 follows second-order kinetics. At 300 °C, [NO2] drops from 0.0100 M to 0.00650 M in 100.0 s. The rate constant for the reaction is M-1s-1. The reaction 2NO2 2NO + O2 follows second-order kinetics. At 300 °C, [NO2] drops from 0.0100 M to 0.00650 M in 100.0 s. The rate constant for the reaction is M-1s-1. 1.2 0.54 0.81 0.096 0.65