Re: CCL:Error estimation of gibbs free energy

["Dr. Richard L. Wood" <rlw28 ^at^ cornell.edu>]

Opps, it should be
 d(dG) = square root([d(dH)]^2 + [T d(dS)]^2)
 so the units come out in kcal/mol (or kJ/mol).
 Richard
 "Dr. Richard L. Wood" wrote:
 > Wouldn't the following be true
 >
 > d(dG) = square root([d(dH)]^2 + [d(dS)]^2)?
 >
 > dG is delta G, d(dG) is the error in delta G, dH is delta H, d(dH) is the
 error
 > in delta H, dS is delta S and d(dS) is the error in delta S.
 >
 > This is taken from a simple error propagation analysis as taught in some
 > physical/analytical chemistry laboratories.
 >
 > Richard
 >
 > Wong Lai Ho wrote:
 >
 > > Dear CCLers,
 > >
 > > I have a question regarding error estimation of the experimental
 values of
 > > gibbs free energy.
 > > As we knows that:
 > > delta G(formation)
 > >    = delta H(formation)
 > >    - Temp * [entropy(molecule)-sum(entropy(atoms to form the
 molecules))]
 > >
 > > Can I claim that the experimental error bar of the gibbs free
 energy(delta
 > > G) is equal to the error bar of the enthalpy change of formation(delta
 H)?
 > > (since the error introduced by the entropy is usually very small)
 > > Is there any papers or books talking about this error?
 > >
 > > I would be grateful if you can give some comments on this claim.
 > >
 > > Larry
 > >
 >
 > --
 > Richard L. Wood, Ph. D.
 > Physical/Computational Chemist
 > Post-doctoral Associate
 > Department of Chemistry
 > Trinity University, San Antonio, TX 78212
 >
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 Richard L. Wood, Ph. D.
 Physical/Computational Chemist
 Post-doctoral Associate
 Department of Chemistry
 Trinity University, San Antonio, TX 78212