Talk:Glycolic acid

Untitled
Does anyone have a pKa or Ka value for glycolic acid as this is what I was looking for specifically. I found at this site a value of 1.47*10-4 which, to my calculations tranlates to a pKa of 3.83 (to 2 decimal places). However, I have no specialist knowledge of chemistry and do not fully understand why there are no 2nd and 3rd values and, if they exist, why not to use them. Some help is required here, thanks in advance! Hydraton31 22:09, 4 June 2006 (UTC)

Typically the pKa of an atom is only in the range of water (0-14), the Ka of the alcohol hydroyl is likely out of the "normal" range.Toby Broom (talk) 19:58, 22 October 2020 (UTC)

Cleanup
I performed a real quick cleanup, but a solid reference for the chembox needs to be indentified so that accurate data can be entered. I haven't checked if hydroxyacetic acid redirects here, but it should.

I'll check back here and edit a bit more when i get a chance

Dakoman 02:28, 8 June 2006 (UTC)


 * Yes, hydroxyacetic acid redirects to this article. As far as I can remember I got all the data in the chembox from a Sigma-Aldrich MSDS. Berserker79 09:48, 8 June 2006 (UTC)

Tattoo removal?
I don't think this article should reference tattoo removal until someone can provide a source that this treatment works or even exists. I am unable to find any information to suggest glycolic acid can help remove tattoos.
 * I agree. Without a reliable source, the information should be removed. (It looks like it already has been.)  It can be added back in later if properly sourced.  --Ed (Edgar181) 16:01, 14 November 2006 (UTC)

External link addition to glycolic.org
There has been a recent addition (reverted a number of times and re-added) of a link to glycolic.org, with the description "Official site". Glycolic acid is a generic name of a chemical &mdash; and does not have an "official site". The referenced external link is to an "informational page" on a site promoting glycolic acid for facial peels. Directly at the top of the linked page is a link for "Store" which leads to the page selling the products. I believe this link is inappropriate as: &mdash; ERcheck (talk) 14:11, 4 March 2007 (UTC)
 * 1) Link to a commerical site.  (Wikipedia is not for advertising.)
 * 2) Inappropriately calling it an "official site", implying that it has some special standing with relation to the topic of the article.

External link to www.kaviskin.com
Removing this. (Wikipedia is not for advertising.) -198.187.174.15 (talk) 13:35, 10 August 2010 (UTC)

Contradiction between text and chembox
There is a contradiction about the solubility in water between the text (It appears in the form of a colorless, odorless and hygroscopic crystalline solid that is highly soluble in water and related solvents.) and the data in the chembox (Solubility in water 0.1 g/mL). My information from "Chemikerkalender" (ISBN 3-540-12652-7) sayea "highly soluble" without further specification. Most chemically related (ethanole, glycole, acetic acid) substances are highly soluble or miscible in/with water. Exept for oxalic acid: 90g/L at 20°C, solide phase H2C2O4+2H2O. "Chemikerkalender" sayes: Melting point 78°C.87.186.126.180 (talk) 13:14, 14 December 2008 (UTC)

Name
The article should explain the nonsystematic name. 121a0012 (talk) 04:34, 21 January 2012 (UTC)

Strecker and Sokolov's first synthesis of glycolic acid
There may be some confusion about how Strecker and Sokolov's synthesis of glycolic acid yielded, as an intermediate, the ester benzoyl glycolic acid (C6H5C(=O)OCH2COOH), as a result of treating hippuric acid with nitric acid and nitrogen dioxide.

(1) According to Wikipedia's article on hippuric acid, treating hippuric acid with acid causes it to hydrolyze into benzoic acid and the amino acid glycine.

(2) According to Wikipedia's article on  nitrogen dioxide, nitrogen dioxide reacts with water to produce both nitric acid and nitrous acid.

(3) Nitrous acid reacts with glycine to produce glycolic acid. See: A.T. Austin (1950) "The deamination of amino-acids by nitrous acid with particular reference to glycine. The chemistry underlying the Van Slyke determination of α-amino-acids," Journal of the Chemical Society, 149-157.

(4) Strecker and Sokolov neutralized the solution of hippuric acid and nitric/nitrous acids, and then concentrated it via evaporation. During the evaporation process, they probably caused the benzoic acid and the glycolic acid to form an ester.

VexorAbVikipædia (talk) 22:25, 1 October 2016 (UTC)