The order, and therefore the rate law, is dependent on the slowest step in a complex (multi-step) reaction.
The expected rate law for a reaction is
Rate = constant * (conc. of A)^n * (conc of B)^n
where A and B are reactants, and n and m are stochiometric coffecients
The mechanism for the reaction of nitrogen dioxide with carbon monoxide to form nitric oxide and carbon dioxide is thought to be
NO2+NO2 > NO3+NO slow
NO3+CO > NO2+CO2 fast
Write the rate law expected for this mechanism. What is the overall balanced equation for the reaction?
3 answers
However, sometimes the powers are not equal to the stochiometric coefficients.
In this case, there is one reactant (NO2) and its coefficient is two.
Rate = k[NO2]^2
In this case, there is one reactant (NO2) and its coefficient is two.
Rate = k[NO2]^2
I agree with Arora for the rate law. The overall equation is the sum of the two steps.
Here is one of the best explanations of how to do these that I've seen.
https://courses.lumenlearning.com/boundless-chemistry/chapter/reaction-
This site clearly shows how to handle the rate law when the slow step is the first step in a multistep proposal as well as when it is not the first step. If you will be doing mechanisms I recommend you study this site thoroughly. It is VERY good in my opinion.
Here is one of the best explanations of how to do these that I've seen.
https://courses.lumenlearning.com/boundless-chemistry/chapter/reaction-
This site clearly shows how to handle the rate law when the slow step is the first step in a multistep proposal as well as when it is not the first step. If you will be doing mechanisms I recommend you study this site thoroughly. It is VERY good in my opinion.