How concentrated can an acid be?

How concentrated can an acid be without it being supersaturated? Is there a certain limit to how concentrated an acid or base can be?


When I mean concentration, I mean molarity; so how concentrated can an acid or base be? 




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**NOTE:** Can be a *strong* or *weak* acid/base. Because we are just looking for the amount of **solvent** needed to dissolve to start the dissociation process.




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**EDIT:** No autoprotolysis please. Acids that **need** a solvent to dissociate.




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> 
> I am talking about dissolving in water since an acid needs some sort of solvent to dissociate.
> 
> 
> 


No, it doesn't. You neglect autoprotolysis where the water-free acid itself is the solvent.


\begin{align}
\ce{2H2SO4 &<=> H3SO4+ + HSO4-}\\
\ce{3HF &<=> H2F+ + HF2-}
\end{align}


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Are you suggesting that if an acid molecule is surrounded by a sufficiently small number of water molecules, then it might display lower than 100% ionization even if it is a "strong acid" ($pK\_a<-1.76$)? That is true; some acids we commonly consider to be strong, such as nitric, hydrochloric or sulphuric acid, will not completely ionize in sufficiently concentrated aqueous solutions, even if there is more than one molecule of water per molecule of acid.


So is there an acid capable of protonating water quantitatively even when there is only one molecule of water per molecule of acid? Yes, in fact there are several. Interesting proof of this is that sufficiently strong acids will form [solid crystalline salts containing the hydronium cation](http://en.wikipedia.org/wiki/Hydronium#Solid_hydronium_salts) when mixed with water in a 1:1 molar ratio. The most striking examples are probably the hydronium carborane salts, such as $\ce{(H3O)^+(HCB11Cl11)^{-}}$. I recommend taking a look at [this fantastic article](http://www.reedgrouplab.ucr.edu/publications/Chem%20Comm%202005%201669.pdf) from the Reed group for details on the wonderful properties of carborane superacids, with a section describing its several salts when reacted with water in different proportions and environments.


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