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Pseudo-First-Order Reaction

Posted: Thu Mar 08, 2018 11:15 pm
by Abigail Urbina 1K
If we are working with a reaction that does not have an overall order of 1, what should we look for to know that we should turn it into a pseudo-first-order reaction?

Re: Pseudo-First-Order Reaction

Posted: Thu Mar 08, 2018 11:27 pm
by Merzia Subhan 1L
I believe the pseudo reactions are always going to be second order but one reactant's concentration is so high so when the one with the lesser concentration runs out, the big one barely changes so you can pretend that it didn't change and that its just a first order reaction with the reactant with the smaller concentration. When [B]o>>[A]o :
(1/[B])ln([A]o/[A])=kt
or
[A]=[A]o*e^(-[B]kt)

effective rate law: rate = k'[B]