Strongest acid known?

[Airmid]

Today I discovered superacids. Wow, this is really cool stuff! I've been reading like crazy, but I'm still left with a few questions. I hope you guys can help me out here.

 

On prof. Chris Reed's page I read that a carborane superacid "can protonate all kinds of molecules that are decomposed by commonly used superacid media".

I wonder what makes carborane superacid so special compared to other superacids. Is this the result of the extreme unreactivity of the carborane anion?

 

I also read that superacids (especially solid ones) are perfect for use as catalysts in industrial processes, because they can be easily separated from the product and reprotonated. Do you think carborane superacids will be recycleable too?

 

And last but not least: I came across a vague reference to a book by prof. Bart Kosko, in which he supposedly said that it might be possible to design superacids that work on some materials but ignore others. What's your opinion about this?

 

I hope I'm not asking for the answer to life, the universe and everything!

 

Airmid.

[woelen]

The unreactive nature of the chloro-carborane anion indeed makes the acids so special. Ultra strong acid, without strong oxidizing or coordinating properties. All other acids also have a corrosive anion, even chloride is very corrosive under the acidic conditions in hydrochloric acid.

 

Unfortunately I have no answer to the second question, maybe someone else.

 

The last thing is not very likely. An acid is strong, or it is not. If the acidic action depends on the counter-compound, then one formally cannot speak of an acid anymore and other methods need to be used for describing them.

[Airmid]

Thanks Woelen!

 

Airmid.

[vrus]

I suppose you probably saw this, but for other people who are viewing this thread :-

 

http://en.wikipedia.org/wiki/Super_acids

 

Some things on that are way way way more acidic than anything mentioned here....

example Fluoroantimonic acid!!!!

[Nevermore]

Fluoroantimonic acid is 2*1016 (twenty quintillion) times stronger than 100% sulfuric acid.

HOLY SH*T!!!!!! :eek:

I guess that's the answer to the op! Wow!

[woelen]

But still, this is not the strongest acid. The chloro-borane based acids, mentioned in earlier posts are MUCH stronger than the acid you mention. I think that that wikipedia page is exaggerating a little. I always though that HSbF6 is about 10^6 times stronger than sulphuric acid and not 10^16 times stronger, but I might be wrong .

[UNCLEBEN]

can anyone tell me what happened when i mixed hydrochloric acid and bleach together and tried to clean the scale off my bathroom with it. I had to evacuate the house for a while as a choking cloud of noxious fumes enveloped me. suffice to say I have left that alone since. It was descaler which i assumed to be acid.

[budullewraagh]

heh, last i checked HSbF6 was 10^18 times more acidic than H2SO4

[budullewraagh]

uncle ben, you made chlorine gas.

 

bleach is 2NaOCl+H2O at equilibrium with 2NaOH and Cl2.

 

when you react bleach with an acid, the equilibrium is pushed to the right as the NaOH reacts with the acid forming a sodium salt and water. as a result, the free chlorine gas is liberated

[woelen]

heh, last i checked HSbF6 was 10^18 times more acidic than H2SO4

Interesting, could you give a reference to the place where this is mentioned. I looked up several tables on the Internet with pKa values for many acids, but I did not find reliable data on HSbF6. Anyway, pKa values for very strong acids tend to be unreliable anyway, because in aqueous solution one cannot distinguish between strong, very strong and ultra strong acids, the observed strength is the same for all of them.

[UNCLEBEN]

Thanks , That Cleared That Up

[nitroglycol]

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.

True of HCl certainly, but nitric acid is actually noticeably weaker. It has a pKa of -1.4, compared to -1.74 for the hydronium ion- so it's only about 93% dissociated in aqueous solution. Which is yet another example of the stronger acid being less corrosive than the weaker one. In this case, what makes HNO₃ so nasty is its oxidizing power, not its strength as an acid.

[John Cuthber]

IIRC telluric acid is a strong enough acid and oxidiser to dissolve gold so there is at least one acid that attacks gold.

 

The strongest acid you can get in any decent concentration in water is H3O+ (or, rather, its hydrated forms)

To get stronger acids you need different solvents. Flurosulphonic acid is already strong but adding a fluoride acceptor like SbF5 to it makes it even stronger.

http://en.wikipedia.org/wiki/Magic_acid

[pioneer]

Fluoroantimonic acid is the king of acids. It is called super acid. It is formed from from one of the former champs antimony pentafluoride.

 

Aqua regia or the queen's bath is still up there. The queen's bath or nitric and hydrochloric is one of the few acids that can dissolve the king of metals, which is often seen as gold due to its color and resistance. Aqua Regia was an alchemist concoction during their research of trying to turn lead into gold. They needed to know the limits of gold before they could figure out how to turn lead into gold. It didn't happen but they did come up with many of the basic chemistry lab supplies of today.

 

What is interesting, the alchemist discovered a non-acid liquid that could dissolve gold. It was the liquid metal mercury. It will form an amalgon and then begin to dissolve the gold if the mercury is the bulk phase. They would then boil the mercury and make the gold reappear. Call EPA. After a few of those experients, dementia would often set in. They took the hit for the gipper and thanks to their personal sacrifice at the alter of early science, they set the stage for the conversion to modern chemistry.

 

Additional Info

 

When I was a development engineer in Oak Ridge, one of my final projects ,before setting out on my own, was to develop the technology needed to decommision the Li isotope separation facility. It used Mercury as the solvent or the continuous phase in the isotope separation. After the system was drained there was still 100,000 pounds to account for. Being a hands-on guy, I would put on the coveralls and explore the historical facility even climbing on top of some of the large equipment. It was sort of dimlly lit and quiet. But during explorations, I could imagine the sound of all the excitement, sort of flashbacks to the busy activity of its hayday. I was fortunate enough to be able to talk to many of the old timers. Their stories fueled my imagination and allowed to see former glory.

 

I considered myself an old time engineer, i.e., fast ideas and experiments, then move on to the next stage. I wished I had been a part of that early development effort. It was a unique time and circumstance, within science, where the scientists led the rapid pace and the beaucrats would play the role of support. One could get the impossible done in record time, since the bearocrats were doing what they did best which was organize and expedite. Even they did the impossible. When beaurocrats play chef the whole process gets drawn out and bogged down, since the mission becomes secondary to political power games. This may be due to less skilled personel leading, and this is their best effort.

 

Because of previous mercury techology, which I had invented in 3 weeks, I was given lead development engineer in this project. I was playfully called the mercury man. This could have been my life's project. The facility was huge. It would have taken decades to recycle, all the way to my retirement, i.e.., assumes beaurocrats chefs leading the charge.

 

Because of my early enthusiasm and cavalier attitude about mercury, such as stories of people walking on pools of mercury with hip boots, it was very likely, I have become over-exposed to the mercury. I began to become more and more off the wall. In retropsect, it was the early stages of dementia. I remember writing a technical report that used alchemy considerations. I am sure it is on file. That went over like a brick ballon. Rather than test me for possible mercury over-exposure, I was treated like I was a rebel and was stripped of my authority to make decisions. I regained some of my equilibrium ,,during a probation period, but was never quite the same. I soon left to pursue an illusion, that I was going to evolve science to another level. What began was an esculation into the deep dark places of the mind. The need for self healing became how I developed my prolific creativity. Where once the unconscious would become spontaneously active, now it is a faithful dog that fetches from the deep layers of the mind. Too much time trying to break the bucking bronco has atropied my social skills. That is why I hide, anonomously.

 

I am not bragging, maybe I am, but I have more direct experience with the workings of the human mind than anyone out there. I did not sit on the sidelines watching others so I could develop my theories. I had to put on the coveralls and get in the trenches and wrestle the beast. If I had to depend on most of the " acceptable stuff" I would gone over the edge. I tried it at first, the stuff was useless under those conditions. I needed to develop things from scratch, while collecting real time, data.

 

I used to go by the screen name "sunspot". I was banished from this forum for being too militant. That was good for me. Maybe I needed to burn out the last of the mercury. I feel more rational now. In retropsect, I began way outside the box trying to get back in. I could not figure how to get past the sentries, so I decided to lay seige. So I surrounded the six sides of the box ,with my armarda of ideas, and started to pound the walls to see if I could make a breech. I had plenty of ammo and I was able to manufacture ammo ideas as fast as I needed to. What I didn't count on, was the box had nukes. They nuked me by pulling the plug. It was actually good for me, because I was having too much fun making war. The last of the dementia was really cranking out the weapons. They weren't all weapons, I was also lofting food and drinks at the same time.

 

After that, I went to the other science forum and the physics forum, with a little more caution, because I thought they might also nuke me. Although I was initially thinking strategy, a seige was not necessary since their wall seemed a more permeable to ideas. This is a teaching forum, so teachers need to limit the scope to help the students build background. They need to keep the walls of the box tighter for the needs of students. The other forums were not as involved in teaching, so the walls of the box were more permeable. This semi-permeable access allowed me to get closer and enter the box. It gave me an opportunity to inspect the walls. I was also able to gain some important recon. Many of those inside the wall would often argued the differences of acceptable opinions. I was able to see points of vulnerabilies much better. At first I figured, rather than barrage the box with saturation bombing, pin-point is better. But it still lead to the problem of the box having nukes to my conventional weapons.

 

As I went further into the box, all miltary strategy became moot. I realized, I not wish to harm what was inside the box, since it seemed good. I was really trying to make the wall more organic. The walls of the box is the like the bark of a tree. This is where the tree grows. If the bark is surrounded by a heart of stone, this will stunt the growth. Maybe my seige had really been directed to the heart of stone.

 

With things inside looking better than expected, I wandered deeper into the box to see if maybe the heartwood was rotten. Maybe there was a type of disease that was eating the heart that required the stone wall. What I came upon was the inner santuary of the box. It was a box inside the box, that had it own fortifications. Its walls weren't defended. The strength of its structure, is the test of time. Being near the walls of the inner santurary brought back memories of the past when I was once allowed to moves freely inside the santuary. It suddenly dawned on me, what I had been trying to do. I had been trying to return home.

[JeffreyTheta]

...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 they`re on the News!

 

While a warning may certainly have been appropriate, there's just no escaping the fact that some people are destined for the Darwin Awards.

[bascule]

This one:

 

[nitroglycol]

Uh... strictly speaking, "acid" is actually a base.

[greysteel_M6]

Fluoroantimonic acid, the dissociation doesn't lie, -25.00!

 

Uh... strictly speaking, "acid" is actually a base.

 

uh... once dissociated

it functions as an acid before it becomes the conjugate base

[nitroglycol]

I was referring to the specific molecule shown in bascule's post. Lysergic acid diethylamide is, well, an amide of lysergic acid. Thing is, lysergic acid is also a tertiary amine, thanks to the nitrogen in the top right of the picture; the acid itself would form a zwitterion in solution like amino acids do. And when you inactivate the acidic part of the molecule by forming an amide, you leave the basic part of the molecule intact. The result is that LSD acts as a base, not an acid; its conjugate acid would be the above molecule with that nitrogen protonated.

[dom3mo]

my dad worked with an acid that was so strong It couldnt be kept in glass because it would melt it. I forgot the name though.

[YT2095]

more than likely HF.

[anbutomo]

any1 wanna help me find 2 chemicals that are easy to get hold of and cause heat but are not flammable

or an acid that causes heat and it not flammable??

 

thanks.

[jacobo]

:doh:HI I AM NEW TO THIS FORUM, SO THIS IS MY FIRST TRY

 

I HAVE A MINING OPERATION, AND WE USE A KIND OF AQUA REGGIA , FOR LIXIVIATION AND HYDROGEN TO RECUPERATE METALS , PRINCIPALLY COPPER AND GOLD.

 

I HAVE JUST READ ABOUT CARBONARE ACIDS, THIS SEEMS TO BE A NICE WAY TO GET RID OF H2SO4, DOES ANYONE HAVE A SIMPLE WAY I CAN PRODUCE THIS TO SEE THE EFECTS FOR LIXIVIATION.???

 

THANKS.

[John Cuthber]

"I HAVE JUST READ ABOUT CARBONARE ACIDS"

Where? I've never heard of them.

(And please stop SHOUTING)

[anpaoliello]

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?

 

http://www.madsci.org/posts/archives/nov99/942956765.Ch.r.html - maybe that?

 

A superacid is an acid with an acidity greater than that of 100% pure sulfuric acid.

Actually, the fluoroantimonic acid is 2 x 10^19 times stronger than H2SO4! It is the strongest superacid known (therefore the strongest acid), and its aqueous solution is about -25 in pH!