Talk:Oxalic acid

message: this chart is from the USDA, 1984.  Several values are inconsistent with current research, notably those that are off by factor of 10 in the publication itself.  For example, carrots are listed as containing .5g/100g oxalic acid, which is 500mg/100g.  More recent studies, such as the one cited for beetroot (https://pubs.acs.org/doi/abs/10.1021/jf048128d) report that raw carrots contain 50mg/100g, which would translate to 0.05g/100g.  There are several significant differences like this that call for a more up to date and comprehensive authority for resolve.
Everydaycurious (talk) 19:25, 7 December 2018 (UTC)
thread_title: Content in Food

message: quote from the article: "In humans, oxalic acid has an oral LDLo (lowest published lethal dose) of 600 mg/kg (human).[11]
The main toxicity of oxalic acid is due to the precipitation of calcium oxalate in the kidneys when urine becomes supersaturated with respect to this salt. Oxalic acid is also a metabolism product of the degradation of ethylene glycol if accidentally ingested and, as such, directly represents a danger for the kidneys in case of glycol poisoning, which can largely be eliminated through the use of propylene glycol based antifreeze products instead for automotive engine cooling."
* what exactly is that last sentence saying about antifreeze used in automotive engine cooling? I think there might be some missing words or information...  — Preceding unsigned comment added by Jraudhi (talk • contribs) 16:31, 26 May 2012 (UTC)
thread_title: Toxicity and safety

message: I fail to see sny carbon int the molecule diagram only ho, o, o, oh wtf is the carbon?? can this be fixed????!?!?!!!?!   —Preceding unsigned comment added by 70.44.21.225 (talk) 15:43, 7 August 2008 (UTC)
replies: text: I'm not a chemist, but it seems to be sort of standard in these diagrams of organic compounds that the carbon isn't labeled; they're at the junctions in the diagram.  There are two carbons in the middle, connected to each other by a single bond.  Each has an OH connected to it by a single bond, and an O connected to it by a double bond.  If that isn't clear, look at the stick and ball diagram.  The carbons are grey.  71.163.32.187 (talk) 22:40, 14 February 2010 (UTC)

text: I came to this talk page seeking an answer to the same question. Having read the above and investigated further, it seems that the answer is supplied here – not only the C but also the H of organic compounds (and maybe even the N and O) can for the most part be assumed without being explicitly indicated, as they can be identified by their different valencies. Vilĉjo (talk) 01:02, 14 November 2011 (UTC)

text: That ought to stick. You can find sugar in everything, but it's hard to find in Coffee.
I can think of four relevant kinds of list: short, long, exhaustive, and complete. Brewhaha@edmc.net 20:12, 7 May 2007 (UTC)
thread_title: Cleanup

message: I found this page  and I merged the parsley and spanish into this page based on   but I coundn't confirm tea nor that cooking increases oxalic acid.  --  W  P Talk 09:19, 18 October 2005 (UTC)
thread_title: Food high in oxalic acid

message: I thought Oxalic acid occurs in every plant, not just "many".  Should this be changed to "all"?  Granted, the concentration varies.  —Preceding unsigned comment added by UMinventor (talk • contribs) 20:43, 24 August 2010 (UTC)
thread_title: Occurrence in nature

message: There is some discrepency between sources on these values. It appears that oxalic acid decomposes at 191 °C, and this is sometimes listed as a melting point: however other sopurces list a lower temperature as a sublimation point. A full review would be welcome, I will do one if I get a chance. Physchim62 (talk) 12:27, 21 December 2005 (UTC)
thread_title:  Melting point/Boiling point 

message: :Some tests for oxalic acid can misidentify ascorbate as oxalic acid.
- What tests...? mastodon 16:06, 23 May 2006 (UTC)
thread_title: Tests

message: The values given as I write this do not specify a temperature. I am replacing them
with 25°C values from 44th ed. of CRC Handbook of Chemistry and Physics and that jibe with values given in 10th ed. of Lange's Handbook of Chemistry. I did find pK values that match what was there (1.27 and  4.27) in Merck Index, but it did not give temperature either. Karlhahn 17:10, 20 August 2006 (UTC)
thread_title: pK<sub>a</sub> Values in Chembox

message: Under "hazards" the LD50 is given as 7.5g/Kg but under safety it's 378mg/Kg.
These are VERY different - which is right?
: .378 g/kg or 7.5 g/kg? That might be a raynj given from animal studies where the Cat and the Rabbit differ, and if so, then that's what should be written. Brewhaha@edmc.net 19:45, 7 May 2007 (UTC)
thread_title:  LD50 

message: I eat sorrel any chance I get - I like its sour taste.
I guess that oxalic acid is as toxic as anything else - if you'll eat too much, you'll not feel good :) —The preceding unsigned comment was added by 87.245.187.51 (talk) 08:55, 26 February 2007 (UTC)
replies: text: The main toxicity of oxalic acid arises from the precipitation of calcium oxalate in the kidneys where it forms kidneys stones and can block the kidneys themselves at high dose. As glycol is oxidized in oxalic acid, it gives the same toxicity problems. A diet too rich in oxalic acid (sorrel, rhubarb, spinach, tomato's, ...) is not good for persons already suffering from the gout disease (acute inflammatory arthritis). Shinkolobwe (talk) 15:50, 29 January 2011 (UTC)
thread_title:  I didn't know it's dangerous 

message: I have tried to add some oxalic acid and some acetic acid into copper(II)carbonate respectively, in order to test their strength. It was quite disappointing to find that oxalic acid react even slower than acetic acid......Is it really true that oxalic acid is "about 10,000 times stronger than acetic acid."? I am frustated with that.Superdvd 09:29, 11 March 2007 (UTC)
replies: text: pH and reaction rates are only related. Copper oxalate is less soluble, so it has to precipitate, too. A better question is whether Oxalate can precipitate Copper(II) out of the Acetate, and Oxalate should be the major product with sufficient time and concentration. I applaud the orijinal research in this case, because it's not part of the article, which should contain more about real world implications. It is a weak acid compared to inorganics. Brewhaha@edmc.net 20:03, 7 May 2007 (UTC)
thread_title:  is it a strong or weak acid??? 

message: "For this reason, a second test for strong reductants using, for example, iodine."
Makes no sense to me. Can anyone explain? Or is it a gramatical error? 82.40.75.55 22:57, 7 June 2007 (UTC)
thread_title:  Bad Sentence 

message: I believe that this article could have included the factors that affect ionisation of oxalic acid.Also oxalic acid yields 2 protons while the other dicarboxylic acids don't yield two protons.Hence the factors for oxalic acid to yield both the protons could have been explained along with Ka values ..
:The chem-data box gives the first and second pKa values, which tell you all you need to know about its diprotic behavior at 25°C. As for other dicarboxylic acids, they too have two pKa values, and thus, some fraction of each of them will yield two protons. See succinic acid as an example. Karl Hahn (T) (C) 12:10, 3 August 2007 (UTC)
thread_title:  The Ionic States of it 

message: This article doesn't seem to mention the melting point or boiling point of Oxalic acid.  Does anyone happen to know what they are?  Larrythefunkyferret 21:56, 12 September 2007 (UTC)
thread_title:  Missing the melting point. 

message: I used to put a tablespoon or so of oxalic acid in my dishwasher to remove hard water stains from my dishes.  At that time I had a dishwasher with a plastic interior. I now have one with a stainless steel interior; can anyone tell me if that is problematic?  I don't want to damage my new dishwasher!  Thanks! 70.146.77.67 (talk) 21:21, 11 April 2008 (UTC)
replies: text: I guess it's easy to experiment and find out. One way to do this would be to pour the liquid into a steel utensil and let it sit there for a while. Observe carefully to see if there is any damage to the utensil. If there is no damage, repeat the experiment for a much longer duration. If there is no damage still, you can also try with hotter oxalic acid if you like. --IO Device (talk) 05:07, 22 March 2009 (UTC)
thread_title:  Use in steel dishwasher 

message: Kiwifruit and taro should be added to the list of plants containing oxalic acid. Badagnani (talk) 05:57, 10 March 2009 (UTC)
replies: text: Does anyone have a cite for this ranking of oxalic acid contents in foods? -Krasnoludek (talk) 21:35, 6 September 2009 (UTC)
thread_title:  More foods 

message: I accidentally spilled oxalic acid crystals on a stainless steel sink. I rinsed the sink and wiped the surface dry and left it about three days. The surface was quite badly pitted especially where it had been previously scratched. It occurred to me that as fiberglass boats and associated wood work and stainless steel are often cleaned with dilute oxalic acid to remove rust stains residual oxalic could remain in stainless steel rigging cables thus speeding up the erosion process dreaded by sailors. Could a warning be placed on this oxalic acid page?Jon Stephen Horridge (talk) 10:49, 9 April 2012 (UTC)
replies: text: We usually avoid giving practical advice (or impractical advice for that matter).  Otherwise these articles would evolve into long lists.--Smokefoot (talk) 12:31, 9 April 2012 (UTC)

text: Would this be a good addition here? - Oxalic acid crystals are used quite often in "associated wood work" and are sold in hardware stores as 'wood bleach'.  In the wood floor world, bleached floors are most often referred to as 'pickled' floors and the use of oxalic acid is part of the process: pickled floor refinishing  EliavresEliavres (talk) 19:25, 21 December 2015 (UTC)
thread_title:  Oxalic acid causes erosion of stainless steel 

message: Ingestion of oxalic acid through skin contact or orally is dangerous.
.
Ingestion...through the skin, makes no sense. Ingestion refers to things taken orally.
70.171.3.221 (talk)BGriffin  —Preceding undated comment added 12:44, 26 July 2012 (UTC)
thread_title:   Ingestion of oxalic acid through skin contact or orally is dangerous. 

message: I am thinking of buying some oxalic acid to use for rust removal.
Please would someone knowledgeable add information about safely disposing of it, in the "Toxicity and safety" section ?  (Which is what I came to this page for.)   Darkman101 (talk) 21:36, 16 August 2012 (UTC)
replies: text: We just are not in the business of giving advice (see WP:NOTMANUAL).  And I wouldn't rely on advice here anyway.  In most countries, suppliers would be required to give information on safe disposal.  If I were disposing of a few ounces, it would go into the toilet because I have a lot of faith in water treatment facilities.  It is toxic to critters, at least until it all gets converted into an insoluble derivative with calcium or iron.  --Smokefoot (talk) 23:31, 16 August 2012 (UTC)
thread_title:  Safe disposal of oxalic acid 

message: I read somewhere that in Japan root vegetables high in oxalic acid are washed in rice vinegar to react out oxalic acid. Anyone know anything about that? I think it would be a good addition to the article.23.16.152.103 (talk) 09:08, 3 October 2012 (UTC)
replies: text: Almost a year late to answer you, but "Effect of Cooking on the Soluble and Insoluble Oxalate Content of Some New Zealand Foods" found that cooking the food items in water helped leach out some of the oxalic acid into the cooking water. "Effect of domestic processing and cooking on selected antinutrient contents of some green leafy vegetables" found similar results and notes that cooking or blanching the food reduced its antinutrient content. For Spinach, longer blanching times resulted in a greater reduction of oxalic acid (they tested 5, 10, and 15 minute blanching times). For Spinach, even 5 minutes of blanching reduced the oxalic acid content by 44%, and 15 minutes reduced it by 65%. Cooking in a pan or pressure cooker was also effective. --Odie5533 (talk) 21:33, 1 September 2013 (UTC)
thread_title: Dealing Traditionally With Oxalic Acid In Food

message: The shown chemical reaction, involving oxygen, is not balanced. Carbonylation is probably correct, but the use of oxygen is unlikely.  — Preceding unsigned comment added by 165.225.72.50 (talk) 12:40, 9 June 2017 (UTC)
replies: text: The reaction appears correct and balanced to me.  And it is an oxidative carbonylation that requires oxygen.  Here's an example in the literature:  http://pubs.acs.org/doi/abs/10.1021/om00081a029  -- Ed (Edgar181) 12:46, 9 June 2017 (UTC)
replies: text: I agree, the reaction is balanced.  It is also patented by Rohm (see US patent 4,713,483).JSR (talk) 12:50, 9 June 2017 (UTC)
thread_title:  Chemistry Shown 

message: Best method to detoxify oxalic acid after using on concrete rust spot removal. Tom Walker (talk) 14:41, 13 November 2017 (UTC)
thread_title:  oxalic acid run off in lawn  after rust removal...sodium bicarbonate neutralization