The reaction between nitric oxide and oxygen is described by the following chemical equation:
2NO+ 2O2 â 2NO2
2NO+ 2O2 â 2NO2 + O

Suppose a two-step mechanism is proposed for this reaction, beginning with this elementary reaction. Suppose also that the second step of the mechanism should be bimolecular. Suggest a reasonable second step. That is, write the balanced chemical equation of a bimolecular elementary reaction that would complete the proposed mechanism.