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Twenty QUINtillion. At least that's what Guiness claimed, and what other websites listed as well. -anonymous user
This page conflicts with
superacid. Superacid says fluroanitmonic acid is only 1016 times as strong as sulfuric acid, but this page says it is 2 times 1019 times as strong. Should a contradiction be flagged on the two pages?
Mathwhiz9060103:00, 4 February 2007 (UTC)reply
It can be stored in teflon containers. Teflon is the single strongest carbon-fluorine bond in chemistry. Otherwise, even messing with fluoroantimonic acid, as much as even exposing it to light, might cause some serious problems. — Preceding
unsigned comment added by
IrisFall (
talk •
contribs)
03:57, 15 April 2017 (UTC)reply
Most strong acids are corrosive. This material is rapidly decomposed in air (hydrolysis) to give
HF, so the question is really, how bad is HF? Ans: bad.--
Smokefoot22:13, 26 October 2006 (UTC)reply
HF I know about. Nasty stuff. Thanks; I was asking since I recalled hearing about some superacid that wasn't corrosive, and knew that HF was more corrosive than HCl, which is a strong acid (this is some serious shit).
129.44.209.6022:17, 26 October 2006 (UTC)reply
It says that Fluoroantimonic acid is stored in teflon. And, I know what one of you were talking about when you brought up another acid that was extremely powerful, and not very corrosive. It's called a carborane acid. But fluoroantimonic acid is pretty much the most corrosive substance known.(UTC)
I glanced at the review but not the original papers. The solvent of choice is
sulfuryl chloride fluoride and apparently in some cases dichloromethane and I think that they cut it with HF to lower the viscosity. I need to look at the actual preps.--
Smokefoot02:41, 30 October 2006 (UTC)reply
Do a Google search for companies that sell chemicals to the general public. HF is a common reagent, as is SbF5. Keep this in mind, however: more or less the only thing it doesn't dissolve is Teflon, and I don't think you actually understand exactly how dangerous this acid is. It fumes when it comes into contact with moisture, like hydrochloric acid but worse, and is supposed to be used under controlled conditions. Its reaction with bases, for example, may be explosive.
Bbi529123:36, 25 September 2007 (UTC)reply
Yeah it's extremely lethal. Basically any exposure of the acid to the human body via breathing or skin contact is going to be too corrosive and too toxic that it is lethal with no countermeasure to survive. The acid can also eat through glass and many other types of containment. It shouldn't be handled directly by humans. I'm pretty sure the chemical engineers use extended pole grippers and mechanical grippers to indirectly handle it and they only handle it if they have to.
70.127.116.20 (
talk) — Preceding
undated comment added
08:25, 28 April 2015 (UTC)reply
"Deprotonation"
As I understand it, the sentence that was just reverted is trying to say "when you react the superacid with a hydrocarbon, you get hydrogen gas expelled from the system, with the hydrocarbon ultimately losing a hydrogen to become a carbocation". There are many words for that, but I don't think "protonation" is one of them. Maybe the article on
protonation is incorrect, but here is an excerpt: "Upon protonating a substrate, the mass and the charge of the species each increase by one unit." It seems to me that the hydrocarbon doesn't *receive* the extra proton - the net reaction seems to involve *losing* a hydrogen it already had. (okay, the superacid is obviously not a base so I can see why you would object to using the word "deprotonation" here, but surely "protonation" is even more misleading? seems to me this reaction is kind of analogous to a hydride group leaving the carbon, rather than what you would call a "protonation")
ugen6406:21, 16 November 2007 (UTC)reply
Ugen64: Great comments. You can see why inorganic chemists use the word 'dihydrogen' for H2, as your words are difficult to parse because hydrogen means H and H2. But in any case, X-H + H+ --> X+ + H2 (where X = any molecular fragment) is not a deprotonation but loss of hydride (H-). Chemists do not really have a single word ("dehydridation") that would be the opposite to deprotonation. Hydrocarbons do this reaction reluctantly, but this acid is seriously strong. And yes as Rifleman points out, the intermediate in H2 loss features pentacoordinate carbon, but we're used to that by now (see
trimethylaluminium).--
Smokefoot13:25, 16 November 2007 (UTC)reply
I doubt it. It'd certainly remove the electrons binding the gold together. But there's nothing to shepherd the gold out, since the fluorines are all tightly bonded. A tiny amount of gold would be dissolved, as with nitric acid, but it wouldn't be removed from the strong attractive forces of the rest of the gold.
--
Ytaker (
talk)
18:30, 16 October 2008 (UTC)reply
I question the pH value given: pH is a function of concentration (e.g., 0.1 Molar solution of HCl has a pH of 1.). Also, unless I messed up my math, this implies something like 10^30 moles of H+ per liter of solution (which I sort of think is physically impossible).
Scienda (
talk) —Preceding
undated comment added
01:31, 8 April 2018 (UTC)reply
Stronger acid
I thing HAuF6 will be even more acidic than HSbF6, since the ionization energy of [AuF6-(10 eV) is much greater than that of [SbF6-(6 eV). Just some thoughts...--
Anoop.m (
talk)
16:20, 28 September 2009 (UTC)reply
Forgive me if I'm totally working on the wrong principles, but here's an idea: HF + CuF11 = HCuF12. If my baseless speculation is right, the
icosahedron shape of the fluorine atoms will make it very difficult for the protons to reattach once they're off. Will the
highly charged ion of Cu11+ do much? —Preceding
unsigned comment added by
72.178.12.19 (
talk)
04:50, 29 September 2009 (UTC)reply
The problem is that
highly charged ions like those in the Sun or in particle accelerators are not "the stuff of chemistry" (by the stuff of chemistry I mean molecules or compounds stable enough that you might be able to hold in a reasonable container, and do "chemistry-like" experiments with them). Once one goes down the road of astrochemistry or particle accelerators, there are many super-duper-acids. The strongest
Lewis acid would presumably be the Uuo118+ cation. For Bronsted acids, the
helium hydride ion has been called the strongest acid. --19:23, 12 October 2009 (UTC)
First of all, (H3O+) is the hydronium ion, not hydroxonium (I'm going to assume that was a typo). Secondly, you are wrong about helium hydride ion simply being a proton carrier; it has been shown to dissociate in water into
He and H+. In fact, empirical data is very evident on this as the proton affinity is shown to be -360 kJ/mol, which is equivalent to an acid dissociation constant of -63, which is 2.52 times stronger than fluoroantimonic acid. Unlike other theoretical compounds which could give higher acid dissociation constant values, the
helium hydride ion is empirically tested and proven so I don't see why it shouldn't be labeled the strongest acid simply because of the environment the ion was created in. —Preceding
unsigned comment added by
173.181.123.136 (
talk)
05:40, 15 December 2010 (UTC)reply
Hmm, thank you. I'd think that Cu11+ would be possible outside of the sun with high heat and fluoride, but looking at the periodic table again, Lu11+ would be more stable. Dropping the idea now.
72.178.12.19 (
talk)
03:08, 23 October 2009 (UTC)reply
It should be noted that no element has been shown to form stable compounds in any oxidation state above +8. That's not to say that such compounds aren't possible, they just haven't been found yet. Eight-coordinate fluoride anions have been found already. One example is XeF8-2, which has a square antiprismatic shape (square antiprismatic coordination seems to be preferred over
cubical coordination for eight-coordinate atoms, since the former is more tightly packed). I'm not sure if HIF8 is possible, but if it is, it might be stronger than fluoroantimonic. It might be difficult to prepare HIF8 due to the fact that
iodine heptafluoride, unlike
antimony pentafluoride, is a gas, and gases are harder to work with.
Stonemason89 (
talk)
19:30, 20 August 2010 (UTC)reply
Would it be better to call fluoroantimonic acid a coordination compound, where hexafluoro-λ5-stibanuide is coordinated through a fluorine to a proton? If that is the case, then is the resulting covalent molecule, zwitterionic or diradical?
Plasmic Physics (
talk)
01:24, 27 February 2011 (UTC)reply
Can't think of any reason to see this as a diradical. When there's a hydrogen sitting on the molecule (SbF6H), then it has some character as a coordination compound, or (perhaps better yet) just a zwitterion with a dative bond between one fluorine and the Sb. The fluorine is then positive and the Sb negative. The hydrogen involved is free to be bonded with a flourine on another SbF6- in a hydrogen bond, as in water (remember flourine is the only other element besides water than can act as the target for a hydrogen bond). As the hydrogen bond gets stronger for one fluorine, the standard bond weakens with the other, until they are equal. Then the hydrogen (H+) is transferred from one fluorine on one molecule, to a fluorine on another. At any one time each SbF6- would be bonded to two hydrogens, linking it to two other SbF6- centers. Again it's very much like water molecules. It's even more like
bifluoride molecules, where the hydrogen is always shared equally in a 3c-2e
three-center two-electron bond. That compound is like an intermediate transition state in the proton transfer "reaction." But as you see, there's not much barrier to such a transition, and that's why the proton is so mobile. However, mobile does not mean floating around in cages of perfectly square planar SbF6- molecules, not particularly associated with any one of them. Any proton is free to bond specially between two fluorines of two different SbF6- centers, drawing them closer to each other, with the hydrogen sitting in bifluoride-like 3c-2e bond between specific fluorines. With that opportunity, no proton is going to go floating through vacuum like it was a big cation in a lattice. The point is that it's not a big cation. It's a proton 1/100,000th the size of the other atoms, but with the same charge. To expect it to behave the same way as a full-sized cation in a liquid, is very naive. But that's what this article held, and what I was told on the
proton wiki. So I came here to protest.
SBHarris04:09, 27 February 2011 (UTC)reply
I agree with your argument, but I diagree on which bond is allocated the title dative bond. Since the hydrogen-fluorine bond is weaker, the dative bond should lie between the fluorine and hydrogen, not the antimony atom. I agree with your charge allocation, within the molecule however, I was uncertain about the degree of orbital overlap. The degree of bond overlap determines whether it is more appropriate to assign a formal charge separation as in a zwitterion, or just leave it as an unpaired diradical. Like we are aware, that distinction can sometimes be difficult, take beryllium oxide as an example. A monomer of beryllium oxide has one covalent bond and a formal charge separation, forming a zwitterion.
According to the article itself, The salts tend to crytallize in dimers with briding halogens, something like digold hexachloride, save that antimony has more valence, so you get diantimony-fluoride-11 anions, with 3c-2e bonds between Sb's and a single bridging fluorine between them, sharing a single set of bonding electrons. The two related products have been crystallised from HF-SbF5 mixtures, analyzed by single crystal X-ray
crystallography, show the formulas [H2F+][Sb2F11−] and [H3F2+][Sb2F11−]. In both salts the anion is Sb2F11−. Go figure. Here the energetics to go to FHF+ and FHFHF+ are so great that they leave the Sb's sharing one fluorine. Still, it's another indication of how much more that H+ would rather be in a 2-D fluorine sandwich or chain, than floating around with nothing.
SBHarris09:39, 27 February 2011 (UTC)reply
I think HSbCl6 would be even stronger because HF is a part of fluoroantimonic acid and HF itself isn't even included as a strong acid.HCl is strong though some folks said Hcl isn't as corrosive.
Just saying. — Preceding
unsigned comment added by
76.124.224.179 (
talk)
23:16, 4 July 2012 (UTC)reply
I'm not a chemist, but the reason why HF is not as strong as HCl as an acid is because of the high charge concentration on the fluoride ion that makes it more attractive the hydrogen ion, thus disfavoring disassociation. However, this is not as important for HSbF6, as the anion is much larger with less charge density.--
Jasper Deng(talk)23:31, 4 July 2012 (UTC)reply
This is an old one that keepds coming up, because people don't read the article properly. The acidity of the substance has nothing to do with with the acidity of HF, it has to do with the bond strength of the fluoride to the pentafluoridoantimony molecule. In any case, what does this have to do with the article?
Plasmic Physics (
talk)
00:19, 5 July 2012 (UTC)reply
Well the acidity of HSbF6 has a lot to do with the acidity of HF. So in principle if one started with a stronger Bronsted acid, and combined it with a strong Cl- binder, one might make something even stronger. So the question is an interesting one, at least to some. --
Smokefoot (
talk)
00:54, 5 July 2012 (UTC)reply
Acidity is a measured property of the substance and has nothing to do with the acidity of the compounds used in the synthesis of the chemical. A simple way to resolve the issue is to compare the Ka's of both materials. Someone has measured the acidity of HSbCl6 in past.
JSR (
talk)
10:20, 5 July 2012 (UTC)reply
"Acidity is a measured property of the substance" I think we got that part. Saying that some property "has nothing to do with" other aspects is simplistic view that divorces logic from the design of molecules. You need to press your teacher on that. Many strong acids arise by the combination of Lewis and Bronsted acids. Viewed this way, the Lewis and Bronsted acidities are relevant to the acidity of the combination.
I've been doing this for 40+ years.... SbF5- is the anion. Not a combination of SbF4 and HF, but a discrete compound. It exotherms when they are mixed, significant chemistry goes on.
JSR (
talk)
19:42, 5 July 2012 (UTC)reply
Exactly. We are concerned only with the pKa of fluoroantimonic acid. I'm not certain if chlorantimonic acid exists.
JSR (
talk)
23:22, 5 July 2012 (UTC)reply
Actually it applies to any solvent system. There are independent acid base systems, as there are many solvent systems. Sulfolane, HF, NH3, etc are all well known solvent systems in which acidities have been measured.
JSR (
talk)
23:35, 5 July 2012 (UTC)reply
I doubt that this material decomposes in water. What is it supposed to do? SbF6- is reasonably happy in water. Yes, the reaction would be exothermic, but that detail is irrelevant. One could say that H2SO4 decomposes in water since the molecule (HO)2SO2 converts to hydronium+SO3(OH)-, but we dont use decomposition in that way.--
Smokefoot (
talk)
13:12, 30 September 2012 (UTC)reply
The reference in the article says otherwise. It is an Olah reference, but I don't have a copy to check. So, if someone does, they can check the veracity of the citation.
JSR (
talk)
13:47, 30 September 2012 (UTC)reply
Your changes make more sense, chemically. Now we need to figure out how to deal with a one sentence safety subsection. I looked and didn't have any earthshaking ideas, but will continue thinking about it.
JSR (
talk)
14:12, 30 September 2012 (UTC)reply
I was surprised to see the new formula too and was ready to accuse Plasmic of OR, but Greenwood and Earnshaw also use that formula. Looks fine to me. I should revise the image, I guess. --
Smokefoot (
talk)
22:16, 28 May 2013 (UTC)reply
In my view that is just a matter o pedantry and doesn't ultimately make much of a difference. If you feel that 'a' works better than 'the', then by all means, don't let me get in your way.
Plasmic Physics (
talk)
04:36, 26 October 2013 (UTC)reply
Simplicity; the fact that protons are never naked isn't really the most important feature here. It's kind of like how you often see H+ written instead of H3O+ when stuff happens in aqueous solution.
Double sharp (
talk)
13:44, 2 December 2013 (UTC)reply
This article is generally about fluoroantimonic acid not only about H2F[SbF6] which we get if we use 2 moles of HF and 1 mole of fluoride...
Mithoron (
talk)
00:40, 12 January 2015 (UTC)reply
Besides, Scientitific Alan was partially right - HSbF6 (1:1) is strongest and there this "naked proton" thing has some sense - there's really H+ coordinated to SbF6 - and source [3] doesn't take this into account. I'm afraid that first part of art. from about 2 years ago had relevant info about it and maybe some of the later edits should be reverted. Somehow we should make it that the art. would take into account various proportions of HF and fluoride.
Mithoron (
talk)
12:58, 12 January 2015 (UTC)reply
@
Plasmic Physics and
Graeme Bartlett: What he means is that the CAS number in the article, 16950-06-4, is specific to the chemical with the formula HSbF6 and is therefore inconsistent with the description of fluoroantimonic acid having the formula H2SbF7.
ChemNerd (
talk)
20:19, 19 October 2017 (UTC):::reply
Carborane acid is 1 million times stronger than sulfuric acid, but fluoroantimonic acid is 10 QUADRILLION times stronger than sulfuric acid. So no, carborane acid is NOT stronger than fluoroantimonic acid.
ScamsAreHorrible172 (
talk)
07:02, 12 October 2017 (UTC)reply
Fluoroantimonic acid is the second strongest superacid, second only to helonium. This should be completely wrong statement. I believe many carborane super acids are stronger than fluoroantimonic acid. Not sure about their silicon and germanium analogues and azaboranes. Neonium (HNe+) should also be much much stronger than HSbF6. Argonium and kryptonium should also be even stronger.
Anoop Manakkalath (
talk)
00:13, 8 December 2022 (UTC)reply
Hydrofluoric solution?
What is this "hydrofluoric solution" that is mentioned in the Safety section? There is no article by that name, while "hydrofluoric" redirects to
hydrogen fluoride, and the only solution of that (using water) is the superacid known as
hydrofluoric acid. Does this mean that "fluoroantimonic acid in a hydrofluoric solution" means mixing fluoroantimonic acid in hydrofluoric acid instead of water (which would be an aqueous solution)?
MarqFJA87 (
talk)
21:34, 6 September 2017 (UTC)reply
'Hydrofluoric' is analoguous to 'aqueous' as used in this context - an 'aqueous solutions is one where the solvent is water, a 'hydrofluoric solution' is one where the solvent is anhydrous hydrogen fluoride, not hydrofluoric acid.
Hmm. I think the term "hydrofluoric solution" is not really correct, as it is not clear whether it means HF with or without water. I will change it to read "hydrogen fluoride as solvent".
Dirac66 (
talk)
14:56, 7 September 2017 (UTC)reply
The space filling image depicts one molecule of hydrogen fluoride, and one molecule of antimony pentafluoride. According to the article, these are the two substances that are mixed together to produce fluoroantimonic acid. Upon mixing, "various cations and anions (the simplest being H2F+ and SbF6-)" are formed. H2F+ and SbF6- are what are depicted in the ball-and-stick image and the letter-and-stick image. I am not an expert in this domain, but presenting these inconsistent images side-by-side without explanation does seem rather silly to me, and obtuse to the point of misinformation.
2601:940:C001:88A0:B186:2D55:CAC6:80A5 (
talk)
23:23, 19 June 2022 (UTC)reply