Catalysts in Rate Law

[Jaden Nguyen 2A]

Other than the example of OH- and H3O+ concentration being the rate law that Dr. Lavelle talked about, is there ever going to be a time where you include a catalyst in the rate law? I remember in high school chemistry I was told that a catalyst would be included, only if in the slow step, because it affected the rate. What Dr. Lavelle said in class was a little confusing.

[Sohan Talluri 1L]

In lecture, I believe Dr. Lavelle noted that catalysts speed up the slow step of the reaction, usually enough that it is no longer the slow step (the reaction would then be limited by a different step). However, if that the catalyzed step still remains the slowest even with the catalyst, then the catalyst would be included in the rate law.

Hopefully this helps and please correct me if there are any mistakes.

[Omar Alkhalili 1J]

Hello! From my understanding there are extremely minimal occasions where catalysts will show up in the rate law.

[Ethan_Choi_2I]

Catalysts only show up if they are part of the reactants in the rate determining step (the slowest step). This is pretty rare, but it does happen.

[Christian Huang 1G]

Hi. I believe that catalysts are included in the rate law if they are involved in speeding up the slow step of a reaction. It also might help to view the overall balanced equation. Just remember that you may see catalysts in the balanced equation but not intermediates. Just some additional information that I hope can help!

[205674360]

Hi!
So catalysts are not usually present in the overall equilibrium reaction, but it can appear in the rate law if the catalyst is a reactant in the rate-determining step, because that makes it a part of the reactants since it is changing the rate.

[Moselle Stieler 3A]

Based on this, a reaction would not be able to be zero order if the catalyst is a reactant in the rate-determining step?

[samaagwani-disc2L]

Hello, catalysts job is to speed up the slow part of the reaction, and only then are they included in the rate law. However, it is rare and catalysts do not always show up in the rate laws. I hope this helps!:)