What is an easy way to remember how to determine if a reaction is first order or second order?
Thanks
First order, second order reactions [ENDORSED]
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Re: First order, second order reactions [ENDORSED]
If a reaction is first-order, it will increase proportionally with the concentration of the reagent. If the reaction is second-order, it will increase 4-fold when the reagent concentration is doubled. There's no real need to memorize them - you can tell based off the superscript (n) on the rate laws if they're given. If the problem doesn't give you the entire rate law, there's usually a way to determine the order.
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Re: First order, second order reactions
Will we ever be asked to do a third or forth order reaction even though it wasn't covered in the course reader?
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Re: First order, second order reactions
We are tested on everything up to page 73 in the course reader. This page ends with "Pre-equilibrium approach".
EmilyLeibovitch2E wrote:Will we ever be asked to do a third or forth order reaction even though it wasn't covered in the course reader?
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Re: First order, second order reactions
Would one of the ways to determine the rate law, if it is not given, be to use initial rates?
Re: First order, second order reactions
Daisy Palomera 3B wrote:Would one of the ways to determine the rate law, if it is not given, be to use initial rates?
I don't see why not
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Re: First order, second order reactions
The rate constant for a second order process depends on the initial concentration of a reactant, whereas this is of no concern for a first order reaction.
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