Talk:Ionic compound

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One metal and one nonmetal required?[edit]

I'm pretty sure this is wrong, I mean look at table salt, (NaCl), this comes from two non-metals, and is definetly an ionic compound.

Your point is correct, but your example is however wrong. Sodium (Na) is a typical metal, but ammonium chloride (NH4Cl) on the other hand is entirely composed of non-metals, as well as choline chloride and a number of other ionic compounds. I will correct this.  :)

-yes it has to be a non metal and non metal. this is because it must have opposite charges. metals have a positive charge, and non metals have a negative charge. Na is a metal, so NaCl has a metal and non metal. :) Na just isnt a tranisition metal, but it is an alkaline metal

what happened?[edit]

This used to much more detailed - what happened it.

What about the properties of ionic compounds, I started writing but some idiots deleted it all.

A GCSE text book is more detailed thanb this.

A level students will find this almost useless.

Someone please rectify —The preceding unsigned comment was added by (talk) 15:04, 5 December 2006 (UTC).

Are you sure you're looking at the right page? I went through the whole edit history and found no substantial deletions of material, and there are no listings in the deletion log either, in case the whole article would have been deleted. Perhaps you wrote in the article about salt, or perhaps you didn't save your changes? (What's the difference between an ionic compound and a salt anyway? I've always wondered, and neither this article nor the one about salt says it explicitly.) // 16:14, 12 December 2006 (UTC)


Shouldn't there be a section on naming of ionic compounds here? 06:00, 28 May 2007 (UTC)waqjan

 Done --99of9 (talk) 04:42, 30 October 2015 (UTC)


I have a problem with this sentence: "Ions can be single atoms, as in common table salt sodium chloride,..." sodium chloride would be an example of an ionic compound, not of a single ion. Anyone willing to rectify this? Prudhommei1 (talk) 04:29, 5 September 2008 (UTC)Prudhommei1

I think the "as in" means "as the components in" not "for example". But yes, it's unclear. I adjusted it a bit to mention components specifically. DMacks (talk) 06:01, 5 September 2008 (UTC)

Untitled Query[edit]

After reading the Ionic Bond page, I find that this article is, while informative, redundant. Maybe this article should be moved to be a part of the Ionic Bond article which is broader in scope.

Elleacampbell (talk) 17:59, 7 September 2008 (UTC)

Electrical conductivity section[edit]

The sentence in this section doesn't make sense (some grammar or typo problem). (talk) 17:01, 21 May 2014 (UTC)

I rewrote the whole thing and added some links to key terms. Let us know if this is clearer or needs more work. DMacks (talk) 17:25, 21 May 2014 (UTC)

Merger proposal[edit]

I propose that Ionic crystal be merged into Ionic compound. These are basically duplicate scopes. 99of9 (talk) 06:38, 27 June 2014 (UTC) Support. All ionic crystals are ionic compounds, and in the solid state at least all ionic compounds are ionic crystals. So there is no reason to have two separate articles. Dirac66 (talk) 02:31, 13 July 2014 (UTC)

Ionic compound vs Salt (chemistry)[edit]

I'm trying to figure out how these two articles should be related. I'll leave some notes here:

  • "Any ionic solid ... is called a salt. In a formal sense, a salt can be thought of as the product of an acid-base reaction"[1]
  • "More generally a salt is the substance produced by interaction of eqiuvalent quantities of acid and base... In general, only the salts of strong acids with strong bases are stable in solution. If either or both constituents are weak, hydrolysis occurs and the solution becomes acidic or basic."[2]
  • "the term salt has come to mean any ionic compound whose cation comes from a base ... and whose anion comes form an acid"[3]

--99of9 (talk) 02:56, 26 March 2015 (UTC)

  1. ^ Harris, Daniel C. (1998). Quantitative chemical analysis (5. ed., 1. print. ed.). New York: Freeman. p. 127. ISBN 0716728818. 
  2. ^ Sharp, edited by D.W.A. (1990). The Penguin dictionary of chemistry (2nd ed. ed.). London, England: Penguin Books. ISBN 9780140512328. 
  3. ^ Brown, Theodore L.; LeMay, H. Eugene, Jr; Bursten, Bruce E.; Lanford, Steven; Sagatys, Dalius; Duffy, Neil (2007). Chemistry : the central science : a broad perspective (10th ed. ed.). Frenchs Forest: Prentice Hall. pp. 104–105. ISBN 9780733974595. 
A belated follow-up. Just today I was looking at this interesting article about drug salts. A skim of the opening paragraphs taught me more about the big picture of that topic, in a way that a chemical layperson like me can easily parse, than I'd ever seen anywhere else, including some reference works that should have offered such info and failed. I have to find time to read the whole thing with due care. In my skim so far I encountered the idea of salts with covalent bonds as opposed to those with ionic bonds. This challenged my shaky grasp, as I had been thinking that even organic salts always had ionic bonds. Anyway, excuse my thinking aloud that probably doesn't add much to the discussion, but I just got excited at finding such an article and had to share my enthusiasm here. Quercus solaris (talk) 01:55, 31 March 2015 (UTC)
Thanks, that supports the idea that the (covalent) product of a soft acid + soft base reaction can reasonably be called a salt. The other possible situation is an ionic compound that cannot be formed with acid-base. My current thinking on this is that although Harris is formally correct, there are some ionic compounds which could not be formed with aqueous acid/base reactions because the ions would be unstable in water. In some cases you may need some imaginary solvent to actually do it. --99of9 (talk) 04:28, 31 March 2015 (UTC)
It is not true that any ionic solid is called a salt. Sodium hydroxide (NaOH) is an ionic solid which no one calls a salt. As for organic salts, they generally have both covalent and ionic bonds. For example, tetramethylammonium chloride, (CH3)4N+ Cl, has covalent H—C and C—N bonds within the cation as well as an ionic N+Cl bond. Dirac66 (talk) 15:31, 31 March 2015 (UTC)
Thanks for engaging Dirac66. Sodium hydroxide is an interesting counter to the Harris quote above. I guess Harris would say that the sodium ion meets the definition of a Lewis acid and the hydroxide ion meets the definition of a Lewis base. Which are you challenging? Or is your point just about common usage? --99of9 (talk) 01:39, 1 April 2015 (UTC)
Common usage. I think most chemists define a salt as the product a Bronsted acid and a Bronsted base. The product of a Lewis acid and a Lewis base is a complex (or coordination complex) if there are distinct molecules, but I don't think this term would apply to NaOH with an infinite crystal lattice.
Your organic salt example doesn't really address the question of whether salts can be non-ionic, nobody doubts that there can be covalent bonds within an ion (even an inorganic ion). A more relevant question is whether a bond between soft-acid:soft-base constituents that is primarily covalent should still be called a salt (e.g. "fluticasone propionate" in figure 1 of the article linked by Quercus solaris, in which a (primarily covalent) ester bond has been formed). Our Salt (chemistry) article currently precludes that, because the first sentence reads "salts are ionic compounds ...". --99of9 (talk) 01:39, 1 April 2015 (UTC)
Ah, now I understand what molecule you meant. But this is also a Lewis acid-base complex so most chemists don't call it a salt. It is usually described as just an ester. Try Googling "covalent pharmaceutical salt", with the quotation marks to specify the exact word sequence.
So for both examples, I think difficulties will be avoided if Wikipedia conforms to the usual definition of salt as the product of a Bronsted acid-base reaction. We could add a note saying that a few authors use other definitions, but it should be made clear that they are a definite minority. Dirac66 (talk) 02:20, 1 April 2015 (UTC)
Thanks. If you find a definition of salt with the word "Bronsted" in it, can you post it here so we can use it as a reference? My dictionary just says "acid". I'm happy to ignore the covalent pharmaceutical salt if it's not even used much in the pharmaceutical industry. --99of9 (talk) 23:58, 1 April 2015 (UTC)
Regarding sodium hydroxide: Wikipedia currently calls it "a white solid and highly caustic metallic base and alkali salt" (my emphasis). --99of9 (talk) 00:10, 2 April 2015 (UTC)

Chemical novice question. Everyone knows that if you drop a chunk of refined sodium metal into a cloud of chlorine gas, you'll get a salt (forcefully so). But can the elemental sodium and the elemental chlorine be considered an acid and a base? If so, which one is which? And if not, then shouldn't the definition of a salt be not "the product of the neutralization of an acid with a base" but rather "a product that can be generated by the neutralization of an acid with a base"? I'm asking this not because I'm hinting at (or fishing for) a Wikipedia edit. I'm just asking with the hope of learning the answers. Quercus solaris (talk) 02:27, 2 April 2015 (UTC)

OK, the 3 preceding edits indicate that we need a simple definition with a source. The best I have is from K.W.Whitten et al., General Chemistry (4th ed., Saunders 1992), p.128 which says A salt is a compound that contains a cation other than H+ and an anion other than hydroxide ion, OH-, or oxide ion, O2-. The preceding two sentences specify that an acid produces H+ and a base produces OH- in aqueous solutions. So I propose we use this definition with Whitten as source. We can add that it this essentially the Arrhenius (not Bronsted and certainly not Lewis) viewpoint.
As for the NaOH article, the word salt there is unsourced and should also be removed as incorrect. There is a reference at the end of the sentence, but it is just a catalog showing that NaOH is commercially available at many concentrations, and it does not contain the word salt.
And for the chemical novice question, I would say that yes, a salt can be generated by the neutralization of an acid with a base, but that this fact should be presented not as the definition but as a statement later in the article. Dirac66 (talk) 02:54, 2 April 2015 (UTC)
Do sodium hydride and water react to form sodium hydroxide (evolving hydrogen gas)? If so, does that not qualify it as a salt? (talk) 16:15, 26 February 2016 (UTC)

Lead section and containing hydrogen ions are acids[edit]

The lead says "Ionic compounds containing hydrogen ions (H+
) are classified as acids,". I find it a little strange to say in the lead, because how many compounds of interst do contain a H+
? I cant remember any! Christian75 (talk) 18:49, 31 December 2016 (UTC)

GA Review[edit]

This review is transcluded from Talk:Ionic compound/GA1. The edit link for this section can be used to add comments to the review.

Reviewer: North8000 (talk · contribs) 18:40, 24 March 2017 (UTC)

I'm starting a Good Article review of this article[edit]

I'm starting a Good Article review of this article. North8000 (talk) 18:40, 24 March 2017 (UTC)

I always like to ask this early, is there someone here who would be involved on behalf of the article? Sincerely, North8000 (talk) 18:42, 24 March 2017 (UTC)
@North8000: yes, I'm around as nominator. Thanks for reviewing. --99of9 (talk) 22:31, 24 March 2017 (UTC)
Cool! North8000 (talk) 15:52, 25 March 2017 (UTC)

GA criteria final checklist[edit]


Passes this criteria. What an excellent job! Does far better at informing the reader than a typical Wikipedia article on a technical topic. The sentences are written so that they natively make clear informative statements, and without having to research the internal links. North8000 (talk) 11:31, 28 March 2017 (UTC)

Factually accurate and verifiable[edit]

Meets this criteria North8000 (talk) 11:20, 28 March 2017 (UTC)

Broad in its coverage[edit]

Meets this criteria. North8000 (talk) 11:19, 28 March 2017 (UTC)

Neutral: it represents viewpoints fairly and without bias, giving due weight to each[edit]

Meets this criteria North8000 (talk) 11:21, 28 March 2017 (UTC)

Stable: it does not change significantly from day to day because of an ongoing edit war or content dispute[edit]

Passes this criteria. North8000 (talk) 18:45, 24 March 2017 (UTC)

Illustrated, if possible, by images[edit]

Has 9 images, all either are in public domain or have suitable licenses. North8000 (talk) 15:55, 25 March 2017 (UTC)
Passes this criteria. Images are well-chosen to enhance the coverage of the topic. North8000 (talk) 11:32, 28 March 2017 (UTC)


Couple of spelling tweaks? I think that the article is in US English but includes "polarised" and "neutralise". I would have changed but wasn't sure. North8000 (talk) 11:24, 28 March 2017 (UTC)

Congratulations, this article passes as a Wikipedia Good Article.[edit]

Congratulations, this article passes as a Wikipedia Good Article. Compared to an typical Wikipedia article on a technical topic, this is very well written and does a better job at explaining a technical topic. Excellent work! North8000 (talk) 11:38, 28 March 2017 (UTC)

Congratulations, this article passes as a Wikipedia Good Article[edit]

(This is "repeated" here for when the review is no longer transcluded)

Congratulations, this article passes as a Wikipedia Good Article. Compared to an typical Wikipedia article on a technical topic, this is very well written and does a better job at explaining a technical topic. Excellent work! Sincerely, North8000 (talk) 11:47, 28 March 2017 (UTC) Reviewer

@North8000: Thanks for the review. Re spelling: Since I was rewriting almost all of the article, and it hadn't been determined earlier, I figured I'd just use my native spelling (Australian English). --99of9 (talk) 12:10, 28 March 2017 (UTC)
@99of9: Cool! Nice work! North8000 (talk) 12:50, 28 March 2017 (UTC)