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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: BFGuru on April 26, 2009, 08:20:45 PM

Title: Catalysts and kinetics
Post by: BFGuru on April 26, 2009, 08:20:45 PM

Hi all.  This is my first post here and I'm hoping someone can help at least point me in a direction without giving me the answer.

I can't seem to find the equation needed to solve this problem and I'm fine working the math, but the actual equation is lost to me.  I've worked it a few ways to no avail so I figure it's time to find some help

Suppose a catalyst lowers the activation barrier of a reaction from 125 kJ/mol to 55 kJ/mol.  By what factor would you expect the reaction rate to increase at 25 celsius? (Assume that the frequency factors for the catalyzed and uncatalyzed reactions are identical.)

Any help anyone can give me would be great.  I'd be glad to share what I have thus far if you like.
Thanks!

Title: Re: Catalysts and kinetics
Post by: Schrödinger on April 27, 2009, 03:43:38 PM

i think i can tell u wat 2 use....

Rate = P*Z*e^{^(-E_act/RT)}
T = temp
e = Napier's no.
R = gas const.
P = probability factor
Z = collision freq.(i am not too sure.)

Title: Re: Catalysts and kinetics
Post by: themedicinebudha on July 03, 2011, 03:31:55 PM

Try using the following equation:

k = Ae^(-Ea/RT)

After performing the necessary unit conversions, you would plug the data into the equation for each circumstance....
that should get you started!