# Strongest acid known?

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Hi everyone...

I have a love for chemitry and some day hope to become a chemist

I have a question: what is the strongest acid known, what is its PH and formula? Are there any prospects for stronger acids to be produced in the future?

Thanks for the help,

Ryan Jones

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I have listed Perchloric acid ( chloric(vii) acid) as being the strongest acid, HClO4.

if you look at acids from the Bronsted Lowry definition, then Fluorosulphuric acid would probably be the "strongest".

however, something like Carborane is even stronger than that, But oddly its not very corrosive at all

I cant comment on the Future....

edit: I just found this: http://en.wikipedia.org/wiki/Carborane might be of interest to you.

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Hi everyone...

I have a love for chemitry and some day hope to become a chemist

I have a question: what is the strongest acid known' date=' what is its PH and formula? Are there any prospects for stronger acids to be produced in the future?

Thanks for the help,

Ryan Jones[/quote']

An acid on its own has no pH. The concept of pH only has sense for solutions of an acid in a solvent (pH is reserved for water as solvent, but the concept can be generalized to any solvent).

Up to recently, fluorosulfuric acid was though to be the strongest acid. This acid has formula HSO3F and it easily splits of its proton, giving SO3F(-) ions and H(+) ions. As I mentioned in another thread, this acid strength is not noticed in water, because in water it splits completely and one cannot observe its real strength.

Recently, however, an even stronger acid is discovered. This is a chlorinated carborane acid, with formula H-CHB11Cl11, where the left H-atom is split off VERY VERY easily as a H(+) ion. This acid is so strong that it is capable of protonating many well-known acids, e.g., when added to anhydrous CH3COOH (glacial acetic acid, which in itself already is quite acidic) the ionic species CH3COOH2(+) is formed!

Yet, this SUPER acid is not really corrosive. The reason of this is that it is only acidic and has no strong complexing, reducing or oxidizing properties. The anion CHB11Cl11(-) is very stable and does not want to react with other compounds. That is what makes this acid only moderately corrosive. In fact, it is less corrosive than simple hydrochloric acid, we can buy at every hardware store.

The acid probably is so strong, that it even is capable of acidifying xenon:

Xe + H-CHB11Cl11 ---> HXe(+) + CHB11Cl11(-)

Would be nice stuff to have...

In water, this acid, however, is not more interesting than e.g. HCl, because it would simply be deprotonated completely at once, just as HCl. Only in quite acidic solvents or in the pure state the strength of this acid can be observed.

EDIT: YT was just earlier, while I was typing this post

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LOL, Woelen, looks we doubled up, while I was editing you were posting, that can only mean that if we Both said the same thing, it MUST be Right!

there you go RyanJ

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Thanks for the infromation guys - very helpful

One more question - what would such a strong acid be used for and what would its PH be in aqueous solution?

Thanks for the information again,

Ryan Jones

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Thanks for the infromation guys - very helpful

One more question - what would such a strong acid be used for and what would its PH be in aqueous solution?

Thanks for the information again' date='

Ryan Jones[/quote']

These carborane super acids at the momemt are not much more than laboratory curiosities, but possible applications are most likely to be found for making new medicines. The extreme protonating capabilities allow the manufacture of new molecules. Bulk applications are not to be expected. The price of the acid cetainly will be much higher than the price of an equivalent amount of gold or platinum.

The question what the pH of an aqueous solution will be cannot be answered without knowing anything about the concentration. But a solution of this acid of a given molarity will not be more acidic than a solution of e.g. HCl or HNO3 of the same molarity. HCl already splits of all H(+) ions, so does the superacid, so in water you'll not notice its superacidity. An acid has an intrinsic strength, but the full strength of an acid cannot be observed in all solvents. Water in fact is quite limiting and all of the acids HCl, HBr, HI, HNO3, HClO4 seem equally strong in water, while in reality there is quite some difference.

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There was one acid in guiness book of world records and said it was like a thousnad times stronger than sulfuric. In what way do you reckon the acid is so much stronger than the h2so4?

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it's actually 10^18 times stronger

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Maybe at one point the acid gets so corossive that it's not corossive; as if the concept of "everything gets stronger" just undoes itself and is reversed.

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Even without the moderation effect of being disolved in water,

you would be hard pressed to beat the elctro-chemical bonds

of chlorine and hydrogen. Able to affix any metallic base and

flood the area with free hydrogen ions.

Beyond the laws that govern the Periodic Table, there could be

a theoretical acid particle, on a sub atomic level. Or some incredible

convoluted chain, that would dissolve at once upon contact. But

all that would be speculation.

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hows that stuff so much more poweful?

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hows that stuff so much more poweful?

I think woelen and YT2095 talked about that in their first two posts

Funny how its less corrosive but in a way I suppose thse coudl eb more useful because of that property, makes them easer to store and use

Must have something to do with my many protons are dissalocated during the dissolving of the substance

Cheers,

Ryan Jones

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Did you guys like my little theory?

no it sucks. jk

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the acids hcl or some super acid both have the same H+, so what does is mean by different protonating capability? is one H+ stronger or something?

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the acids hcl or some super acid both have the same H+, so what does is mean by different protonating capability? is one H+ stronger or something?

No, all H(+) ions are equal. Some acids, however, are more equal than other acids .

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No, all H(+) ions are equal. Some acids, however, are more equal than other acids .

Thats quite confusing but I tink I get what you mean

Are there any acids that will dissolve gold? I have heared of one called aqua reiga which is a mixture of a few (two?) acids but are there any others?

Cheers,

Ryan Jones

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Thats quite confusing but I tink I get what you mean

I was teasing akcapr a little, that's all.... He should read the responses a little more carefully and be less in a hurry, and then he'll grasp the concepts.

Are there any acids that will dissolve gold? I have heared of one called aqua reiga which is a mixture of a few (two?) acids but are there any others?

Aqua regia is a concentrated 3 : 1 molar ratio of HCl and HNO3. This dissolves gold by formation of chlorine and nitrosyl chloride. The gold is dissolved by means of a strong oxidizing action and complexing action.

Another liquid (not an acid) which dissolves gold easily is a solution of NaCN or KCN, which is kept in contact with air intimately. Again, the combination of oxidation (oxygen being the oxidizer now) and complexation (cyanide being the ligand) results in quick dissolving of gold. Probably a mix of NaCN and H2O2 also is capable of dissolving gold.

Any strongly oxidizing liquid, with chloride or cyanide as complexing agent can dissolve gold. An example is 30% H2O2 + 30% HCl + a little bleach.

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Yeah, gold is actually pretty reactive, but the Au(+) ion is very easily reduced back into gold metal. So when you put gold into a normal acidic solution, some of it will dissolve but it will immediately go right back to metallic gold as the Au(+) ion quickly eats up electrons and forms a metal again. With the chloride ion present, you can stabilize the Au ions by forming the AuCl4(-) anion. Gold is much 'happier' in the +3 oxidation state and the chloride ions are able to stabilize the gold, thus allowing more gold to go into solution and the net effect is your gold is dissolved. The problem is, you need a pretty good oxidizing agent to put gold into a +3 state; hence why nitric acid is used.

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Any strongly oxidizing liquid, with chloride or cyanide as complexing agent can dissolve gold. An example is 30% H2O2 + 30% HCl + a little bleach.

ROFLOL, and do NOT do this mix either!, its potentialy lethal.

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ROFLOL, and do NOT do this mix either!, its potentialy lethal.

I presume you mean blech and Hydrochloric Acid there? I've mixed some things together but I tend to stay away from mixing things like acids with things that I don't know exactly what they are such as bleach

Or did you mean Hydrogen Peroxide and Hydrochloric Acid.... Or was it Hydrogen Peroxide and bleach... :S

Cheers,

Ryan Jones

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HCl and bleach isnt a great combination outside a fume cuboard

the addition of H2O2 can only make maters worse, the real danger is the "Bleach", not ALL of them are NaOCl based when bought from a shop.

a good many things sold as toilet cleaners contain a variety of "garbage", I wouldnt take my chances.

not only that, but you have to respect that this thread is PUBLIC and not aimed at just you, someone could come along a year or more later and read it, and think "Hmm.. bleach= cleaning product... I have some Ammonia for cleaning my windows too" next thing ya know theyre on the News!

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HCl and bleach isnt a great combination outside a fume cuboard

the addition of H2O2 can only make maters worse' date=' the real danger is the "Bleach", not ALL of them are NaOCl based when bought from a shop.

a good many things sold as toilet cleaners contain a variety of "garbage", I wouldnt take my chances.

not only that, but you have to respect that this thread is PUBLIC and not aimed at just you, someone could come along a year or more later and read it, and think "Hmm.. bleach= cleaning product... I have some Ammonia for cleaning my windows too" next thing ya know theyre on the News![/quote']

Good point, I say that on the news before... this woman mxed a few cleaning agents together, left then in the sun in a closed room and went out - when she came back there was quite a mess

Cheers,

Ryan Jones

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ROFLOL, and do NOT do this mix either!, it`s potentialy lethal.

YT, you're right. I should have given the warning.

In the hands of someone, who does not know its properties it is a really dangerous mix. I use this mix sometimes, but I know that it is dangerous and should only be used outside or in a good fumehood and it should only be made at ml-quantities.

OK, you lost me.