Talk:Clausius-Clapeyron relation

Thanks for creating this article

I created two redirects to this article: Clausius-Clapeyron equation and Clausius-Clapeyron relation. Both redirects use the ordinary dash ( - ) on our keyboards. The difference between that and the dash that I think you used is ( - – ). Most readers will probably use the keyboard dash to search for this article. Anyhow, thanks for creating this article. Milton Beychok 17:33, 11 September 2009 (UTC)

Suggested revision of lead-in sentence

Paul, to me, a single-component is a single pure compound like say butane and liquids like gasoline or an aqueous solution of ethanol (which are mixtures of compounds) are not single-component systems. In the lead-in sentence, should it be revised to say "...an equation for a system consisting of two phases of matter in ..." rather than the current "...for a single-component system consisting of two phases in ..." ? Milton Beychok 15:50, 12 September 2009 (UTC)

Milt, I must confess that I don't have any hands-on experience with the C-C relation. But reading about it, I got the impression that it applies to single (pure) components only. At least the derivation is for pure systems, because it deals with only one chemical potential μ. It seems to me that for mixtures the proof must be extended with more μ's. Do you know anything about that?--Paul Wormer 16:16, 12 September 2009 (UTC)

I also don't have any direct experience with a multicomponent C-C equation, but during my research for the Heat of vaporization article, I found these references:

• A Russian (Belarussian) journal article This includes a preview explaining a "Clausius-Clapeyron equation for multicomponent systems"
• Lucknow University (India) By authors in the Physics and Chemistry departments. It includes their version of a "Modified Clausius-Clapeyron relation for ideal multi-component mixtures"
• Clapeyron Equation for Multicomponent Systems" A NASA paper
• Paper by Wayne C. Edmister Discusses the use of the use of a "multicomponent Clapeyron equation". Wayne Edmister (now deceased) was the one of the most eminent experts on the thermodynamics of hydrocarbon systems back in the time when I was doing refinery process design.

Unfortunately, I cannot access the last two of the above references without paying for them. Perhaps they are avilable to you via your university.

If you decide to tackle those references, perhaps they might be the makings of a separate multicomponent C-C article.Milton Beychok 20:20, 12 September 2009 (UTC)

Just another suggestion

Paul, if you changed all of the II's into L's and all of the I's into V's throughout the article and the drawing caption, it would make it much easier for readers to keep up with which phase is liquid and which phase is vapor ... which seems to have been causing you problems as well. What do you think? Milton Beychok 08:41, 15 September 2009 (UTC)

No Milt, I don't want to do that, because the relation holds for other transitions as well. I intend to add a (qualitative) phase diagram for liquid-solid-gas (triple+critical point in it). It will show 3 lines and for all three C-C holds. --Paul Wormer 06:40, 16 September 2009 (UTC)