Talk:Compressibility factor (gases)/Draft

There is an article of the same name on Wikipedia

Despite the same name, this article was written completely from scratch. Any similarity with the WP article is purely coincidental. - Milton Beychok 21:15, 2 April 2008 (CDT)

EOS

Milton, would it be possible to sketch briefly the pros and cons of the different EOS's? I finished reading and I'm ready to approve the article. --Paul Wormer 12:50, 5 April 2008 (CDT)

Paul, thanks very much for findimg all those typos and for adding a few bits information as well. I must have read it a dozen times and I still had some typos!! I would still like to wait, at least a week for other editors (if any) who may have comments, before you nominate the article for approval.

As for a comparison of the EOS's, I tried that when I was writing the article but couldn't come up with anything that I liked. Some are better in certain areas but not as good in certain other areas. So I decided to say no more than the following (in the section on "Modified versions of the van der Waals equation"):

Perhaps the most commonly used equations of state by engineers working in petroleum refining, petrochemical production, natural gas processing, cryogenic distillation and related industries are: the Redlich-Kwong equation developed in 1949, the Soave-Redlich-Kwong equation developed in 1972 and the Peng-Robinson equation developed in 1976. Those three equations are essentially modified versions of the van der Waals equation.

If you have some wording to suggest other the above, I would be pleased to have you send it to me. Milton Beychok 21:15, 5 April 2008 (CDT)

Notation of powers

You write $T^{2.5},\quad T^{0.5}$ instead of $T^{2}{\sqrt {T}}$, and $\quad {\sqrt {T}}.$ The first notation implies that other powers are OK too, say T^2.6, but I can imagine that dimensionality arguments only allow exact square roots. If that is the case then the second notation is preferable. If the exponents (2.5 and 0.5) are more or less coincidental (i.e., give best fits) then the first notation is preferable, but a remark about this would be in order. --Paul Wormer 13:31, 14 April 2008 (CDT)