Coefficients for the rate of reaction

[405112316]

Why is that you can use the coefficients from a reaction in the rate law for elementary reaction but not other types of reactions?

[Chem_Mod]

You can only do this for an elementary reaction because that is the only step that leads to your products. With other reactions, the overall reaction often times contains multi-step mechanisms that are not shown, therefore the rate would be dependent only on the slow step of the mechanism.