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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: oscabat on January 09, 2005, 04:54:21 PM

Title: Chemical Kinetics
Post by: oscabat on January 09, 2005, 04:54:21 PM
So, my teacher gave me these two problems out of the book that ask for the rate law.
O3(g)----->O2(g) + O(g)
O3(g) + O(g)----->2O2(g)

I know the rate law formula is something like
rate=k(O3)(O)
(I used the second equation as an example), but I can't figure out what order the reactants are, or how you would find these.  Help?
Title: Re:Chemical Kinetics
Post by: gabeser0117 on January 10, 2005, 03:11:28 AM
rate laws are quite simple...
you need to set the up equal to rate, like you did

rate=k[O3] thats it... if you need to calculate it, then you need the mol/L of O3
 
someone correct me if im wrong.. (thank God i had my notebook next to me)



to find the order of reactants you would need the data of the reaction....
for example, if
initial [O3] is .010 and initial [O1] is .010 and the rate is 1.20x10E-3, then
in another experiment,
initial [O3] is .020 and initial [O1] is .010 and the rate is 2.40x10E-3....
O3 is order 1, and O is order 2.

Hope this helps
sorry for the [O1] thing, but if i put [ O ] it looks like this (look below)
Title: Re:Chemical Kinetics
Post by: Donaldson Tan on January 10, 2005, 05:38:25 PM
I know the rate law formula is something like
rate=k(O3)(O)
(I used the second equation as an example), but I can't figure out what order the reactants are, or how you would find these.  Help?

you are right if the mechanism for breakdown of ozone is so. first verify the mechanism of the breakdown of ozone before you "guess" the rate law.