Presence of a Catalyst

$aR \to bP, Rate = -\frac{1}{a} \frac{d[R]}{dt} = \frac{1}{b}\frac{d[P]}{dt}$

Matt_Coopersmith_4H
Posts: 20
Joined: Wed Sep 21, 2016 2:57 pm

Presence of a Catalyst

How do you write the rate law reaction when a catalyst is present? After finding the rate law reaction, do you include the catalyst into calculations to find k, the rate, or various concentrations? Thanks!

Mihika Sridhar 3H
Posts: 11
Joined: Wed Sep 21, 2016 2:58 pm

Re: Presence of a Catalyst

hi matt! Step by step reactions with catalysts look like this (the catalyst cancels out in the final balanced equation):
Step 1: A + Cat. --> Int.
Step 2: Int. + B --> D + Cat.
Final: A + B --> D

when a catalyst is added, the energies of R and P are unaffected, only the activation energy (Ea) is affected, so the value of k (Arrhenius equation: k = A*e(-Ea/R*T)) and the overall rate equation would change