I Review | Learning Goal: To understand how elementary steps make up a mechanism and how the rate law for an elementary step can be determined. Very often, a reaction does not tell us the whole story. For instance, the reaction Submit NO2(9) + CO(g)→NO(g)+ CO2(9) does not involve a collision between an NO2 molecule and a CO molecule. Based on experimental data at moderate temperatures, this reaction is thought to occur in the following two steps: Part B 1. NO2(9) + NO2(9)→NO3(g)+N0(g) 2. NO3(9) + CO(9)→CO2(9) +NO2(9) Which species is a reaction intermediate? • View Available Hint(s) Each individual step is called an elementary step. Together, these elementary steps are called the reaction mechanism. Overall, the resulting reaction is NO2(9) + CO(9)→NO(9) + CO2(9) Notice that in the elementary steps NO3 appears both as a product and then as a reactant; therefore it cancels out of the final chemical equation. NO3 is called a reaction intermediate. Also notice that 2 molecules of NO2 appear in the reactants of the first step and 1 molecule of NO2 appears as product of the second step, the net effect leaves only 1 molecule of NO2 as a reactant in the net equation. Submit Molecularity is the proper term for "how the molecules collide" in a reaction. For example, step 1 is bimolecular because it involves the collision of two molecules. Step 2 is also bimolecular for the same reason. Unimolecular reactions involve only one molecule in the reactants. Though rare, collisions among three molecules can occur. Such a reaction would be called termolecular. Part C What is the rate law for step 1 of this reaction? Express your answer in standard MasteringChemistry notation. For example, if the rate law is k[A][C]3 type k* [A] * [C]^3. • View Available Hint(s) Rate = Submit Part D What is the rate law for step 2 of this reaction? Express your answer in standard MasteringChemistry notation. For example, if the rate law is k[A][C]3 type k* [A] * [C]^3. • View Available Hint(s) Rate = Submit Provide Feedback