Talk:Acid dissociation constant

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1 List of pKa values and compounds
2
3 Table of pKa values
4 cleanup
5 Separate basicity constant article
6 pKa H2S
7 Basicity formula
8 Article Cleanup Co-Ordination Point
- 8.1 Discussion
9 1/3 of the way there
10 Wonky intro

[edit] List of pKa values and compounds

Why is there a list?

good question - it just adds length to an article that is already too long. Would anyone mind if I removed it? Conrad.Irwin 17:30, 21 March 2007 (UTC)

[edit]

shouldn't the last be pKe = pKa + pKb?

Yes, it should be. In addition, this page would probably be better placed under "acid dissociation constant" or simply "dissociation constant." I need to look up what my nearest chemistry book calls it. --ES2 19:00, 19 Aug 2004 (UTC)

In this case, Ke = Kw , so pKe = pKw = pKa + pKb

H Padleckas 15:09, 10 Apr 2005 (UTC)

It is wrong that the adicity constant ranges from 0 to 1. If the acid is almost totally disolved, the acidity constant will tend to infinity. It is true though, that the constant will tend to 0 if there is werry little disolution. /Asger Krüger 9 Nov 2004 This has been fixed. H Padleckas 15:09, 10 Apr 2005 (UTC)

[edit] Table of pKa values

Something looks wrong in this table of pKa values. Why are a bunch of bases listed in what should be an acid's table? H Padleckas 15:17, 10 Apr 2005 (UTC)

Theres really nothing 'technically' wrong with listing a pKb as a pKa as long as you know the difference, I'm going to have to call the whole table suspect now. Phosphate doesn't have a pKa or a pKb, phosphate is an ion. It is not a compound. Same goes for Borate. I'm further suspect now because all those amines that are listed could be compounds, but they could also be organic groups. I vote we strike the table and include a reference to the link currently labeled number one in a "See Also" section. EagleFalconn 21:40, 10 Apr 2005 (UTC)

Couldn't we put "ammonium" and "pyridinium," for example, instead of "ammonia" and "pyridine"? Olin

We could do it for ammonium, but that wouldn't work for pyridine. To my knowledge, a protonated pyridine is just called...a protonated pyridine. EagleFalconn 05:54, 8 February 2006 (UTC)

Actually, a protonated pyridine IS called pyridinium! Olin

[edit] cleanup

I performed a cleanup and got rid of a lot of redundant and wordy (in my opinion, at least) information. I don't think I changed the content of the article, just tried to make it more precise. Olin

[edit] Separate basicity constant article

Shouldn't there really be a different basicity constant article? Olin 22:27, 18 February 2006 (UTC)

[edit] pKa H2S

When clicking the link for Hydrogen sulfide in the pKa table (listed at 7.00), the specific article says the pKa is 6.89. A pretty big difference. Someone who knows for sure should change one of the articles.

It's not as big a difference as it seems, and it is a value which has not been measured (to my knowledge) for several decades... Physchim62 (talk) 08:34, 7 June 2006 (UTC)

[edit] Basicity formula

Inthe basicity formula, it reads: A–(aq) + H2O(l) ⇌ HA(aq) + OH–(aq)

Shouldn't the "A" (that I'm guessing means acid, at least in the acidic formula) be changed to B? B–(aq) + H2O(l) ⇌ HB(aq) + OH–(aq)

No. Once the H+ leaves, what is left is an acid, regardless of the direction of reaction.

[edit] Article Cleanup Co-Ordination Point

Cleanup Co-ordination
	This article has recently been tagged as requiring cleanup to meet Wikipedia's quality standards. The article may have been flagged as needing cleanup because it has been suggested that: the article needs formatting, proofreading, or rephrasing in comprehensible English. the article has multiple overlapping problems. the article is very short and might need expanding, removal or merging with a broader article For a full list of possible problems see Wikipedia:Manual of Style. As part of the cleanup process, the automated bot PocKleanBot has generated this notice as a focus of cleanup efforts, and also contacted several contributing editors of the article to bring their attention to the problem. You should use this section to discuss possible resolution of the problem and achieve consensus for action. Only when there is a consensus that the article is now cleaned up should you then de-list it by deleting the cleanup tag from the article, this causes the article to drop off the monthly cleanup-needed list page.
[edit] Discussion

Cleanup Co-ordination

This article has recently been tagged as requiring cleanup to meet Wikipedia's quality standards.

The article may have been flagged as needing cleanup because it has been suggested that:

the article needs formatting, proofreading, or rephrasing in comprehensible English.
the article has multiple overlapping problems.
the article is very short and might need expanding, removal or merging with a broader article

For a full list of possible problems see Wikipedia:Manual of Style.

As part of the cleanup process, the automated bot PocKleanBot has generated this notice as a focus of cleanup efforts, and also contacted several contributing editors of the article to bring their attention to the problem. You should use this section to discuss possible resolution of the problem and achieve consensus for action. Only when there is a consensus that the article is now cleaned up should you then de-list it by deleting the cleanup tag from the article, this causes the article to drop off the monthly cleanup-needed list page.

[edit] Discussion

[edit] 1/3 of the way there

Hi, I have majorly rewritten the first part of this article - but after that, I dont understand what it is on about. I dont know whether someone who does understand could perhaps simplify what is there. I was going to add some stuff about the stability of the ion affecting it - but I am not sure if that is covered under Factors that determine the relative strengths of acids and bases. Acidity in non-aqueous solutions seems to be a bit example specific and I am not sure of its relevance. I hope that what I have done is OK, and hope someone can help with the rest.

Conrad.Irwin 17:27, 21 March 2007 (UTC)

I have recently re-written the core articles chemical equilibrium and equilibrium constant. I've now started to clean this one up, so far having done definitions and useage. I intend to do the rest in the next few days.

I wonder whether weak acid and strong acid should effectively be deleted by transferring the distinct content here and making them into redirects to this article. Any thoughts?

Petergans 16:34, 18 May 2007 (UTC) Finished the revision. Can we now go for concensus?Petergans 19:38, 19 May 2007 (UTC)

[edit] Wonky intro

The intro says pKa applies to weak-acids. This is news to me, and futhermore pKas are supplied for strong acids later in the entry. --Belg4mit 21:55, 1 October 2007 (UTC)

I understand your point. The difficulty is that pK can only be measured when there is partial dissociation, that is, when the acid is "weak". The pK of a "strong" acid such as HCl must be measured in a medium which is more acidic than water.Petergans 06:41, 2 October 2007 (UTC)