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#Post#: 1070--------------------------------------------------
Equation derivation
DIR By: Chemist@
Date: November 8, 2012, 7:06 am
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How is the following equation derived:
ln(k2/k1)=-ΔH/R*(1/T2-1/T1)?
It is similar to Arrhenius', but where does the entalphy change
come from?
#Post#: 1071--------------------------------------------------
Re: Equation derivation
DIR By: Michel
Date: November 9, 2012, 2:22 am
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This relation is true for a reversible reaction. recall that for
a reversible reaction,
dH=Eaf-Ear
where Eaf= Ea for forward reaction
Ear=Ea for reverse reaction
due to difficulties in formatting the equation in the forum, i
have attached the derivation as a Pdf. See the attachment below
#Post#: 1075--------------------------------------------------
Re: Equation derivation
DIR By: Chemist@
Date: November 9, 2012, 6:48 am
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I see that at the end I get equilibrium constants and not rate
constants. Nicely explained, thanks very much.
#Post#: 1079--------------------------------------------------
Re: Equation derivation
DIR By: Michel
Date: November 9, 2012, 10:50 am
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Of course, there are still many assumptions. for instance we
assume the arrhenius factor,A is approximately the same for both
forward and reverse reactions. and the value of A may also vary
slightly with temperature. but these can be safely ignored
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