What is the world's strongest acid?

Question

I mean in the sense of corrosion. Like what is the worst possible acid that could do damage to living tissue, paper, clothing, anything? Like you know that alien movie where acid corrodes through everything so fast, I know thats not real but what is the closest acid that could do that?

Answer 1

The strength of an acid or base is how well it dissociates (comes apart to create hydrogen ions or hydroxide ions, respectively) in water. The so called strong acids dissociate very nearly completely, meaning that every molecule of acid yields a hydrogen ion. The six strong acids are perchloric acid, hydroiodic acid, hydrobromic acid, hydrochloric acid, sulfuric acid, and nitric acid.

Hydrofluoric acid, while not one of the strong acids, is the most corrosive acid. It it the most reactive acid, and will even eat through glass.

Answer 2

HF is actually not terribly strong as an acid.  It seems strong, because the fluoride etches glass, because it can penetrate skin and do lots of serious damage, and because the acid can be used as a pure liquid as opposed to a water solution.  But even HCl is a stronger acid.  Concentrated sulfuric acid is the strongest common acid, and relatives of it such as trifluoromethanesulfonic acid are stronger still.  But there are a class of 'super acid's which are much stronger.  They're all fluoride acids of some sort.  I think the strongest is H SbF6.  "Magic acid" fluorosulfuric acid and SbF5 mixed, so this is a similar acid.  The superacids are so acidic that hydrocarbons are bases in their presence.  Such things as hexane and methane can be protonated and made to undergo carbocation reactions in superacid.  

In the way you're looking at it, damage to materials, the superacids aren't really practical.  Chloride causes iron corrosion, so HCl is probably the worst from that point of view, and nitric is the best in general at just 'eating' metals.  For organic materials, nothing beats hot sulfuric acid. It might just give you your Hollywood-type effects.

Answer 3

strongest acid---- lsd52

Answer 4

HF is MEAN STUFF. It requires special handling and can be deadly.

I think you want conc sulfuric acid, however. Turns sugar to a carbon foam in a flash. Typical chemical "magic" trick. Sucks the water right of things even when that water is chemically bound as in a carbohydrate (sugar).

Answer 5

There are no substances that quite equate to "movie acids".  They don't dissolve people and they don't dissolves safes.  I do a demo where we add H2SO4 to sugar and get a column of black carbon being formed.  That's because H2SO4 will "dehydrate" sugars, removing water molecules, and leaving the carbon behind.  Similar nasty things can happen to a person's flesh.  HF is also nasty, not because it is a strong acid, but because of the way that it can react with calcium in the body.

There are also a few misconceptions in this thread that should be cleared up.

First there are the common laboratory strong acids:

HCl, HBr, HI, HNO3, HClO4, and H2SO4.

To be an acid, these must be dissolved in water.

H2SO4 is only a strong acid with regard to the first H that dissociates. HSO4- is a weak acid.

"Pure", concentrated (uncombined with water) H2SO4 is not a strong acid at all.  Strong vs weak refers to the degree to which the acid dissociates to form H+ and anions.  "Concentrated" H2SO4 is not dissociated and is therefore not "strong" until it is actually combined with water.

Hydrofluoric acid, HF, despite being a "nasty" acid, is a weak acid because it does not dissociate completely in water.

The "worlds' strongest acid" is fluoroantimonic acid, "HSbF6".  It is an exotic "super acid" that only exists in aqueous solution.  There are no molecules of HSbF6.  It only exits as a solution of SbF5 dissolved in HF.

Someone mentioned that the strongest acid had a pH of -25.  That is impossible, since pH is a measure of the hydrogen ion concentration.  The -25 is the estimated pKa of HF/SbF5.

By the way, it's always a good idea to avoid plagiarism.  When someone cuts and pastes an entire section from Wikipedia, then credit should be given to the source, and not passed off as your own writing.

Answer 6

Acidity depends on the concentration and therefore, the anwer can vary. Depending on the concentration, HCl can have the pH level of 1 or -1. Generally, Fluoroantimonic acid can be described as the most acidic substance since it can be as low as -25.

Answer 7

Corrosion in your terms of damage is separate from strength when applied to systems like the body. Hydrofluoric acid is a weak acid, but a potent poison. It is painless on contact, yet quickly binds with magnesium and calcium in your body, destroying bone and tissue. Imagine removing the steel supports out of the empire state building...not a pretty sight.

But corrosion on single surfaces (metal, wood, etc.) is a little different. This isn't some intricate body that depends on little bits and pieces of itself to work, now its down to brute strength. Fluoroantimonic acid, the strongest acid known to man, probably takes the cake.  

Answer 8

no. hydrochloric acid.

make it a good day