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Topic: Maxwell distribution  (Read 7400 times)

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Offline zeshkani

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Maxwell distribution
« on: September 01, 2007, 07:22:45 PM »
my question is this
 what fraction of CO2 molecules have a kinetic energy between 1.0eV - 1.1eV at 1000k
on the problem set it says to use the maxwell distribution of speeds, but there is no way this can work for kinetic engery, if it was velocity its easy,
i mean the formula for maxwell is this

f(v) =4pi(M/2piRT)3/2*v^2 e-^(Mv^2/3RT)

but just dont see where kinetic energy fits in this equation

Offline Yggdrasil

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Re: Maxwell distribution
« Reply #1 on: September 01, 2007, 10:34:54 PM »
Two options:

1) Use the maxwell distribution for kinetic energies (you can probably find this in some p-chem textbook).

2) Calculate the range of speeds associated with CO2 molecules moving within that range of kinetic energy.

Offline Borek

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Re: Maxwell distribution
« Reply #2 on: September 02, 2007, 04:17:12 AM »
First of all - how is speed related to kinetic energy?
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Offline zeshkani

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Re: Maxwell distribution
« Reply #3 on: September 02, 2007, 12:13:49 PM »
KE=1/2mv^2 ;D

ok i think i got it but iam not sure

so i converted 1.0eV - 1.1eV to Jouls and i used KE=1/2mv^2 to calculate velocity

so (V1)= square root{(1.60218e-19)(2)/(44.01)}
 V1= 8.532e-11 m/s

and V2= square root{(1.76239411e-19)(2)/(44.01)}
 V2= 8.94936e-11 m/s

does this seem to be the right way on doing this

Offline Yggdrasil

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Re: Maxwell distribution
« Reply #4 on: September 02, 2007, 02:48:26 PM »
Check your units.

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