Talk:Entropy of mixing

message: This page is truly terrible. Proof "let's imagine things on a lattice" how can you start a proof with that? As far as I know the world does not exist on a lattice. However, I think the confused nature of the page just reflects a lack of consensus in general on this.  —Preceding unsigned comment added by Cplowe1 (talk • contribs) 22:01, 18 June 2010 (UTC)
thread_title: Lattice comment

message: One small question of style. What does it mean when two dates are given for the same reference, as Callen 1960/1985 and several other examples? My guess is first edition 1960, edition consulted 1985. However I was taught to just identify the edition consulted (e.g. 4th edition 1985) and forget the original edition. Dirac66 (talk) 23:49, 12 July 2011 (UTC)
replies: text: You are probably right for the context in which you were taught, and perhaps also for the present context. Perhaps it is a bad habit that I like to briefly indicate to the reader that there is a history to the publication. I don't see it as very harmful here, even if not according to the rules and regulations.Chjoaygame (talk) 00:48, 13 July 2011 (UTC)
thread_title: Notation for publication dates

message: To Chjoaygame: I agree with most of your latest edit, but the statement that "Ideal materials do not have intermolecular forces" requires correction. It is true that ideal gases and mixtures of ideal gases do not have intermolecular forces. However all liquid (and solid) solutions must have intermolecular forces in order to provide cohesion as a liquid (or solid) - with no forces a liquid solution would just evaporate. A liquid solution will be ideal if all the intermolecular forces (A-B, A-A, B-B) are the same, so that a given molecule "sees" no difference between its A neighbours and its B neighbours. This is explained correctly in the ideal solution article. If a molecule does see a difference between its neighbours, then the interactions are "specific" and the solution is not ideal. Dirac66 (talk) 00:44, 19 July 2011 (UTC)
replies: text: Thank you. Advice followed.Chjoaygame (talk) 03:41, 20 July 2011 (UTC)
replies: text: This point is correct now. However I am not happy with the phrase "ideal material", which is added several more times in today's edit. I have never seen it used to mean "ideal gas or ideal solution". Googling "ideal material" leads instead to many solid materials which are supposedly ideal for constructing various objects. I would rather use the standard terms and say "ideal gas (mixture) or ideal solution" where appropriate. Dirac66 (talk) 23:27, 26 July 2011 (UTC)
replies: text: Thank you. Advice followed.Chjoaygame (talk) 23:43, 26 July 2011 (UTC)

text: On second thoughts, I spoke too soon. It seems too rigid to rely upon a Google survey to dictate what words one should use. The words 'ideal' and 'material' are not copyright or proprietary trademarks, but are words of ordinary language. I will try a compromise, because to repeat the phrase "ideal gas (mixture) or ideal solution" too often would attract a criticsm of clumsy anaphora.Chjoaygame (talk) 23:50, 26 July 2011 (UTC)
replies: text: OK. At least now we have defined our non-standard vocabulary. (And I had to look up anaphora.) Dirac66 (talk) 00:23, 27 July 2011 (UTC)
thread_title:  Ideal liquid solutions do have intermolecular forces 

message: The article now freely interchanges \Delta S\, and \Delta S_m\, to mean the same thing. For consistency and clarity, I propose to change to \Delta S_{mix}\, throughout. This is in agreement with the referenced textbooks by Atkins and de Paula, and by Rock, as well as with the IUPAC Green Book. It is clearer than \Delta S\, which could refer to any process, and clearer than \Delta S_m\, where the m could mean molar.  Dirac66 (talk) 18:10, 27 July 2011 (UTC)
thread_title:  Notation - clearest subscript is "mix" 

message: Good point, necessary correction. Thank you, Dirac66.Chjoaygame (talk) 00:53, 28 July 2011 (UTC)
thread_title: Total entropy of a system

message: Call me old-fashioned if you like, but it makes me very unhappy to see the word 'random' introduced in this way. The notion of randomness belongs to statistics and is not in the home territory of macroscopic thermodynamics. If you want to put something about statistical mechanical explanations of thermodynamics, that is to say, some statistical thermodynamics, into the lead, I would prefer it to be done explicitly in a new paragraph rather than see it done by slipping in a phrase that I feel is out of place.
The concept of 'randomness' is not as obvious as perhaps one might be led to think by some of its users. It is often used, I think, as a substitute for clear thinking and expression. It should be used carefully.
I am not about to overwrite your present edit but I would like to ask you to revise it.Chjoaygame (talk) 21:06, 4 August 2011 (UTC)
replies: text: I accept that talk of intermolecular forces is not part of macroscopic thermodynamics. For that reason perhaps they should be put into a separate paragraph, like talk of randomness. I have made an attempt along these lines.Chjoaygame (talk) 21:41, 5 August 2011 (UTC)
replies: text: OK, the two levels of the discussion are now separated. I have just added the words "On a moleculsr level" as a clear signal to the reader that this is the start of the molecular discussion. Dirac66 (talk) 22:07, 5 August 2011 (UTC)

text: Yes.Chjoaygame (talk) 22:24, 5 August 2011 (UTC)
thread_title: "Random mixing"

message: The new intro sentence was overly long so I have removed a few words which seemed less essential. I am still trying to understand the phrase separate systems ... of different and chemically non-reacting chemical substances or material components, are mixed .... What is the difference here between a chemical substance and a material component? Could we say instead separate systems ... of different composition are mixed without chemical reaction ...? This seems not only clearer but also more general as it is includes the case where (some or all) substances are in common but in different proportion, for example the mixing of air with pure oxygen gas. Dirac66 (talk) 20:07, 18 June 2013 (UTC)
replies: text: Yes, I agree. Well said. I suggest you go ahead and make the changes.Chjoaygame (talk) 22:37, 18 June 2013 (UTC)
thread_title:  Chemical substances or material components? 

message: I have edited over the previous edit which read: "Almost everywhere we look, we find empty lattice cells. But we do find molecules in those few occupied cells."
That previous version does not make sense. The word 'those' in it has no naturally defined reference. One has to infer that it refers to the non-empty cells implied by its first sentence, though they are not explicitly indicated in that first sentence. Such an expression is sometimes called unresolved anaphora. Use of the word 'those' presupposes that some determinate reference object is immediately present. In unresolved anaphora, that is not so, and the reader has to guess to resolve the anaphora. Mostly this will constitute a fault of style or even of grammar.
Since this point has arisen once already just recently with the same editor, and the meaning was not clear to the editor 75.0.185.27, and my edit to correct it apparently did not convey the message, it may seem that the new extension of wording is perhaps necessary. Alternatively, in the previous version, that editor 75.0.185.27 edited over, the word 'those' referred to cells identified in the same sentence; thus it was acceptable in style and grammar, so that the edit was unnecessary.
It would be good if editor 75.0.185.27 would give himself a user name. So far as I know it is safe to do so. And it makes it happier to talk with him.Chjoaygame (talk) 00:13, 1 December 2013 (UTC)
thread_title:  a few occupied cells 

message: The last two sections of this article, "Mixing under other constraints" and "Gibbs' paradox: 'mixing' of identical species versus mixing of closely similar but non-identical species" appear to contain a lot of forceful editorializing. They seem to be extensively-referenced opinion pieces. In particular, they seem to avoid any re-interpretations provided by Jaynes (in the 1950's! A long time ago!) and seem to adamantly argue for conclusions that have not obviously withstood the test of time (despite the dozen citations and references given!) The article on Gibbs paradox does give Jaynes the time of day (even though that article is problematic, but in a different way), and the article on entropic force gives at least some hints where the work comes from/goes to (even though this is also a controversial topic.). It doesn't help at all that these sections aren't decorated with any diagrams showing where these permeable membranes are located, what direction they move in, how far they move, what forces are applied, and what the temperature gradients and heat flows might be. We've got P,V,S,T and maybe a chemical potential or maybe not, some enthalpy or maybe not, but they're all tangled up in the prose. Overall, it comes off as an opaque opinion piece, rather than trustworthy information. I'm not happy about that. It doesn't smell right. FWIW, exploring the article history, it appears that these sections were added by User:Chjoaygame between 2011 and 2014. He/she has clearly made prolific contributions to this article. Failing to address Jaynes is perhaps the most serious issue. Opaqueness due to missing diagrams is also problematic. I can't figure out what the deal is. 67.198.37.16 (talk) 02:00, 20 May 2024 (UTC)
replies: text: Thank you for your care for this article. I am a keen admirer of Jaynes, and am sorry that I didn't give him adequate notice. Great to add some diagrams. I am not a fan of the term 'entropic force'. I always feel more comfortable with Wikipedia editors who select and use a user name, which may preferably be chosen to preserve anonymity or security.Chjoaygame (talk) 02:56, 20 May 2024 (UTC)
replies: text: You are welcome to call me 'Linas'. I'll reiterate: as currently written, it is not obvious that the content in those sections is actually correct. It's also not obvious that a sentence-by-sentence dissection would be a good use of time. So, I'm not sure how to proceed, other than to call attention to it. 67.198.37.16 (talk) 04:53, 21 May 2024 (UTC)
replies: text: Thank you for your response. I was suggesting that you give yourself a Wikipedia user name. Then it is obvious to all that they are conversing with a definite person, as distinct from a web address. I suggest you choose one that doesn't risk your privacy or security. Of course, you are free to improve the article as you please.Chjoaygame (talk) 19:47, 21 May 2024 (UTC)
replies: text: My wikipedia user name is Linas. Editing from an IP address offers strong advantages over editing from a WP login. This is generally understood by all. Nothing to do with anonimity nor privacy. If you wish to have personal conversations, we can have them on my personal talk page. Doing this in article space is not appropriate. 67.198.37.16 (talk) 20:58, 21 May 2024 (UTC)
thread_title:  Editorial opinions in the article