Question

Explain why the coefficients of an elementary step equal the reaction orders of its rate law but those of an overall reaction do not.

Short answer

When two molecules collide, an elementary step is created in a single step. The rate of an elementary step is proportional to the product of the concentrations of the reactants with the same exponents (order) as the stoichiometric coefficients in the equation for this step. The complete reaction may have a number of such stages with varying speeds. On the other hand, the speed is computed using the slowest step. As a result, the reaction orders of its rate law do not necessarily match the stoichiometric coefficients of the overall equation.

Step-by-step solution

Step 1: What is the reaction of an elementary?

A chemical reaction in which one or more chemical species react directly to create products in a single reaction step and with a single transition state is known as an elementary reaction.

Why do the coefficients of an elementary step match the reaction orders of its rate law

The collision of two molecules creates an elementary step in a single step. The product of the concentrations of the reactants with the same exponents (order) as the stoichiometric coefficients in the equation for this step is proportional to the rate of an elementary step. A number of such phases with varying speeds may be included in the total reaction. However, the pace is calculated using the slowest step. As a result, the reaction orders of its rate law do not always match the overall equation's stoichiometric coefficients.