Catalyst in rate law?


Moderators: Chem_Mod, Chem_Admin

rkang00
Posts: 69
Joined: Fri Sep 28, 2018 12:25 am

Catalyst in rate law?

Postby rkang00 » Sat Mar 16, 2019 7:05 pm

Is having a catalyst in the rate law allowed? Or is it not, like intermediates aren't?

Nicole Garrido 2I
Posts: 52
Joined: Fri Sep 28, 2018 12:18 am

Re: Catalyst in rate law?

Postby Nicole Garrido 2I » Sat Mar 16, 2019 7:10 pm

They could be included because they are present in the original reactants. But i'm not sure because in class we learned that catalysts are not consumed so they in may cancel out.

Ashish Verma 2I
Posts: 59
Joined: Fri Sep 28, 2018 12:28 am

Re: Catalyst in rate law?

Postby Ashish Verma 2I » Sat Mar 16, 2019 7:26 pm

Well they aren't present in the final equation but are in the initial step so I suppose they could be in the rate law for one specific step but not the overall rate law? But I'm not sure honestly, sorry.

Cienna Henry 1J
Posts: 61
Joined: Fri Sep 28, 2018 12:15 am
Been upvoted: 1 time

Re: Catalyst in rate law?

Postby Cienna Henry 1J » Sat Mar 16, 2019 7:52 pm

Catalysts can be in the overall rate law. See Lyndon's Pork Ramen review question 14f for an example

Angela Cong 3C
Posts: 69
Joined: Fri Sep 28, 2018 12:25 am

Re: Catalyst in rate law?

Postby Angela Cong 3C » Sat Mar 16, 2019 7:56 pm

Catalyst can be present within the rate law

Andrew Bennecke
Posts: 62
Joined: Fri Sep 28, 2018 12:15 am

Re: Catalyst in rate law?

Postby Andrew Bennecke » Sat Mar 16, 2019 11:45 pm

You can have catalysts present in the Rate Law, but you can't have intermediates because they only exist for an instant and therefore don't affect the rate, but must instead be substituted using the steady state approximation (Not for the final) or the pre-equilibrium approach.

Jonathan Omens 1K
Posts: 60
Joined: Fri Sep 28, 2018 12:15 am

Re: Catalyst in rate law?

Postby Jonathan Omens 1K » Sun Mar 17, 2019 5:48 pm

A catalyst can be present in the rate law if it is a reactant in the rate determining step. Because it is a reactant in that step, it is included in the rate law.


Return to “Reaction Mechanisms, Reaction Profiles”

Who is online

Users browsing this forum: No registered users and 1 guest