Hello, I have been doing Lee/Kesler correlations ad nauseum to compare with calculated values for residual enthalpy and entropy with the Redlich/Kwong equation. My enthalpy values have varied as much as 400 J/mol with the correlation compared to the equation (enthalpy's in the 2500 J/mol range). My question is why do I care about these Lee/Kesler correlations if they aren't even that accurate (assuming Redlich/Kwong is accurate) or vice versa if Lee/Kesler is accurate. Also, why are these equations so horrendous for calculating the residual enthalpy and entropy with RLK? There is so much number crunching for it.