Talk:Acid
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[edit] Older discussions
"Acids in Foods"? Some of these acids are *NOT* used in foods, so the list is misleading.
Norm
In the article it says that the word for acid comes from both "Arabic Azait meaning oil" and "the Latin acidus meaning 'sour'". I think perhaps it would be good to clarify that a bit, because at the moment it's somewhat contradictory.
Here it says that the generic formula for an acid is AH, but I've also seen HA. Is it worth mentioning that it can be either? Or is it only supposed to be AH?
- I think it's a naming convention for some acids. For example, you usually say HCl not ClH. Then again, according to WebElements the Hill system formula is Cl1H1. Maycontainpeanuts 14:04, 12 Oct 2004 (UTC)
Correct me if I'm wrong, but I believe H3O + is outdated like ammonium hydroxide (the hydronium ion doesn't exist) and the equation should be 
or something like that. Maycontainpeanuts 14:04, 12 Oct 2004 (UTC)
It depends on what particular theory of chemistry you happen to follow. The one you're speaking of is the Arrehnius theory, where all acids are explicitly compounds that can release a hydrogen ion. The Bronsted-Lowry Theory includes some other molecules that also exhibit acidic/basic behavior, and also explains the behavior of Arrehneius acids/bases. Example: HCl is an Arrhenius acid, 
but is also adequately explained by the BLT (heehee) 
. However, the Arrehneius theory doesn't explain the behavior of some weak acids/basis, such as acetic acid or ammonia. Also, HA or AH doesn't matter.
That said, virtually all chemistry textbooks I have seen (and I mean well over two dozen) give the generic formulas as HA (or HX in the case of HCl, HI, etc.). So I would strongly recommend switching it around. stismail
- I agree with you, so I took the liberty of switching this round. I also changed - to −, and → to ⇌ for these equilibria. Nearly all browsers now render these symbols correctly, and better a ? than an incorrect symbol. The whole article could do with a rewrite, IMHO, but I don't have time to do it myself at present. Walkerma 16:03, 30 August 2005 (UTC)
[edit] Suggest 4 possible wiki links and 1 possible backlink for Acid.
An automated Wikipedia link suggester has some possible wiki link suggestions for the Acid article:
- Can link tomato sauce: ...or '''[[ethanoic acid]]''': (E260) found in [[vinegar]] and tomato sauce... (link to section)
- Can link oxidation state: ...ifferent from redox reactions in that there is no change in oxidation state.... (link to section)
- Can link organic acid: ... and the acidity of the proton-donating-compound, called an organic acid, is determined by its stability when it donates protons to ... (link to section)
- Can link crude oil: ...ub> is the amount of [[titration|titrant]] (ml) consumed by crude oil sample and 1ml [[spiking]] solution at the equivalent point... (link to section)
Additionally, there are some other articles which may be able to linked to this one (also known as "backlinks"):
- In Henri Braconnot, can backlink acid properties: ... by Fourcroy (1806). Unfortunately, he did not observed its acid properties which led [[Chevreul]] to discover in 1820 [[stearic acid]]...
Notes: The article text has not been changed in any way; Some of these suggestions may be wrong, some may be right.
Feedback: I like it, I hate it, Please don't link to — LinkBot 11:30, 1 Dec 2004 (UTC)
- I went ahead & added the one for oxidation state because it seemed relevant and worth adding. The others I did not add as they didn't seem as pertinent to the chemistry conversation. --Dawn Burn 04:33, 19 June 2006 (UTC)
[edit] Chloric Acid
Under Strong Inorganic Acids, Chloric acid is mentioned. But when I clicked on Chloric acid's article, it states that Chloric acid is a weak acid.
What is it, strong or weak?
- It depends on your definition, actually. The most fundamental and logical definition of "strong acid" is "an acid which, in aqueous solution, is a better proton (H+) donor than the hydronium ion". Because the Ka of hydronium is equal to the molarity of pure water (about 55), this definition requires an acid to have a Ka of over 55 to qualify as strong. Because the Ka of chloric acid is about 10, it is a weak acid by this definition.
- On the contrary, many chemists treat it as a strong acid because, in all but the most concentrated aqueous solutions, the majority of its molecules are dissociated. User: Nightvid
[edit] Acids in food
I think that for the "Acids in food" section, folks here need to decide whether or not they want to have fatty acids included. These types of "acids" aren't generally thought of as acids because in the forms we generally find them - with glycerols attached - they don't disolve in water, have much of a Ph, etc. But I saw that stearic acid was included on that list. For consistency sake, it should either be removed, or the other common fatty acids, such as oleic and linoleic, should be added. Maybe a separate list? I dunno...
There actually doesn't seem to be any discussion of fatty acids at all in the article, which I find a little odd, as they are one of the more notable oddities in the world of acids - with oils and fats paradoxically being made of acids and yet having a neutral Ph. --Blackcats 06:58, 15 Apr 2005 (UTC)
[edit] "Acids and Bases" template has foreign language entries
| Acids and bases: |
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Acid-base reaction theories |
Why does the {{Acids and Bases}} template in this English Wikipedia have some entries in it written in a foreign language resulting in red links? Looks like German to me. It was not always this way; somebody changed it, but I don't know where this template can be edited to change it back. To the right here is what the display of the template looks like in this article and several others related to acids and bases. I think it should be changed back to the English language restoring the links. H Padleckas 13:08, 6 August 2005 (UTC)
- I fixed this problem by editing the template back to English.
H Padleckas 08:22, 9 August 2005 (UTC)
[edit] able to give up a proton (H+ ion) to a base
I think this phrase in the first paragraph could do with being expanded a little. What does "able to give up" mean exactly? --Rebroad 07:36, 13 August 2005 (UTC)
[edit] What Makes an Acid Acidic
A Question:
What makes an acid "acidic." More specifically, what about the free floating protons that makes an acid behave the way it does? What about the chemical characteristics of an acid that makes an acid "burn" through certain objects (e.g. clothes), but unaffect others (e.g. glass)?
Just Curious
- So, regarding this. What those free floating protons do is react with things that can accept positive charges or have localized excess negative charges. The reason it'll burn through things like clothes is because of the structure of the chemicals that make clothes, whereas glass isn't reactive in the same way. As far as inserting this in the article, perhaps it could be put under reactivity? It really doesn't seem to be address specifically anywhere I could think of looking (Acid, proton etc) EagleFalconn 05:07, 22 January 2006 (UTC)
- Kuestion - H2SO4 is a liquid in room temperature, right? If it is, then if there's a solution with 100% H and SO4 ions, would it still be an acid? Eg would it still burn through stuff? or do you need H20 (water) in the solution to make it an acid?--Number 8 00:49, 23 January 2006 (UTC)
- Err, no. At room temp, H2SO4 just sitting out is a solid. If it were a liquid, if you were to heat it for example, it would still still be just H2SO4. 'cept it would be a liquid. H2O or some other polar solvent is required to turn it into sulfuric acid.EagleFalconn
[edit] acid number
I moved the acid number, which seemed specialized, to that article. Olin 23:39, 18 February 2006 (UTC)
[edit] move stuff to acid dissociation constant
Some of the material here should probably be moved to acid dissociation constant. The text here is almost longer than that article! Olin 23:43, 18 February 2006 (UTC)
[edit] strong acids merger
About 95% of the material in strong acids is already here, hence the feelers on the merger. Olin 22:13, 2 March 2006 (UTC)
Polyprotic Acids are not all Strong acids (eg. OP(OH)3)
- Holding to the belief that strong acids are essentially a subset of acids in general and limited down to only 6 or 7 acids anyway, I see no reason there needs to be a seperate article. The difference between weak and strong is the amount of ionization that occurs. However if the concern of SuperAcids is addressed, they are more complicated compounds that derive from salts of acids and other lewis acids, hence the need for superacids to have a seperate page. Das_Nerd posting from 205.160.180.4 22:07, 20 April 2006 (UTC)
[edit] Intro seems majorly incorrect
It says "An acid (often represented by the generic formula HA) is a water-soluble, sour-tasting chemical compound that when dissolved in water, gives a solution with a pH of less than 7", but that's a highly Arrhenius-centric description and is explicitly contradicted by the "Definitions" section. Water-solubility is certainly not a requirement: many carboxylic acids are sparingly soluble at best). And lowering of pH only applies to certain definitions of acidity (aqueous ammonia is basic but NH3 is a fine Brønsted-Lowry acid in the presence of a strong enough base).
The definitions section seems to do an adequate job of introducing that there are different ways of thinking about this whole issue. Scrap the intro sentence altogether? DMacks 19:21, 6 March 2006 (UTC)
- In reality you're right, although in many ways I'd prefer to keep it the way it is (which is contradictory, I know!). I think to the average laymen, this page (and a lot of chemistry pages) are too complicated, whereas that one sentence is easy to latch on to, and for that person, his/her average encounter with an acid would be such compound. On the other hand, if you deleted it, I definitely wouldn't be put up a fuss. I think there should be some generic paragraph at the beginning to keep with Wiki standards. I did a lot of editing on this article a few weeks ago, and I appreciate your comments. Olin 19:40, 6 March 2006 (UTC)
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- I rewrote this, trying to keep the simplicity while keeping it correct. Is it better now? Walkerma 19:59, 6 March 2006 (UTC)
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- I just hacked on it a bit more. Separated the idea of acidity (lower pH) from an effect of that (sour taste) that many consider a hallmark of acids. DMacks 20:10, 6 March 2006 (UTC)
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"Acids generally taste sour; however, tasting acids, particularly concentrated acids, can be dangerous and is not recommended." Why is an encyclopedia making recommendations at all, let alone such a manifestly ridiculous one as this? "is not recommended" by whom? does this mean I should stop eating citris?
- Hacked this out for now. It seemed quite misplaced (and badly written) for the intro. Perhaps some note of common acids in foodstuffs within the main article would be better? (Or have I just missed this?) --Plumbago 16:16, 23 September 2006 (UTC)
[edit] Inorganic acids
I think it would be a good idea for someone to create INORGANIC ACIDS article. Wikipedia HAS the article about the organic ones but not about inorganic...
-I added this subject to the requests, i think "Inorganic Acids" can also be merged with the "Acid" article when it has been created user:Kiptrev
[edit] Solution
All the acid data here is based on water solutions, but couldnt we add how to turn acids constants and data from normal water solution to anyother solution? Like if you have liquid ammonia solution water is the acid and other weaker bases becomes acids and such
[edit] Its caracteristics
shouldnt there be a section for the caracteristics of an acid and a base? paat 21:01, 17 June 2006 (UTC)
[edit] Constants
I think we should add how to calculate the acid/base constant for the acid/base, not its conjugate only
[edit] pH
Why p is small letter and H is capital letter
- The "p" means "base-10 log", and I think is always loewr-case in that meaning. Why? Dunno...why not? The thing we're calculating the log of is hydrogen concentration: "H" is the chemical symbol for hydrogen, and is capitalized because chemical symbols always are. By the same pattern, it's common in medicine to talk about pO2 and pCO2. DMacks 17:18, 19 July 2006 (UTC)
[edit] Common household liquids, ranked by acidity
I think the article could use a list of commonly consumed liquids, ranked by acidity. Acidity is something we can directly experience by taste. Could just list it like Lemon Juice, Coffee, Coca Cola, Water, Milk, Mylanta (assuming I got the order right. Mathiastck 17:25, 17 August 2006 (UTC)
