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Topic: Rate law for reaction with many steps  (Read 1519 times)

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Offline Woopy

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Rate law for reaction with many steps
« on: June 23, 2013, 11:25:49 PM »
Hello,

I ran into a problem with a rate law that includes 5 steps

step 1 is an equilibrium reaction with a k1 and k-1

next is step 2, when is k2 and is the slow step

steps 3-5 are fast

My question is, why for the rate law do I need to think about the equilibrium reaction? Shouldn't the rate law depend only on the slow step?

Offline curiouscat

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Re: Rate law for reaction with many steps
« Reply #1 on: June 24, 2013, 01:07:10 AM »
My question is, why for the rate law do I need to think about the equilibrium reaction? Shouldn't the rate law depend only on the slow step?

Your slow step will have species in its elementary rate expression that are intermediates. The final rate law needs to be clean of these intermediate concentrations.

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