Strongest Acids

Discovered in 2004, the world's strongest acid is carborane acid with the formula H(CHB11Cl11). Its anionic part (the part without the acidic proton)looks like this:

It is hundreds of times stronger than the previous record-holder, HFSO3(fluorosulfuric acid--also known as sulfurofluoridic acid), which has the following structure:
Carborane acid releases its proton very easily but the remaining anion is conveniently not corrosive due to its high stability. This is not true of other acids such as HF where the negative fluoride attacks silicon in glass.


Enrico: See footnote 2, which tries to explain (ineffectively) that the proton is not shown. It depends on the phase. In the solid state, the acid is a polymer with Cl---H+---Cl bridges. In the gas phase, the acid is a monomer with the proton bridging the 12 and 7 positions (farthest from CH) although the 7,8 isomer is probably also present. In solution, it will typically be ionized to give a disolvated proton, H(solvent)2(+), and the free a CHB11Cl11- anion shown in the picture. See JACS(Journal of Amercian Chemical Society) 2006, p3160. Perhaps you'd like to update Wiki? Sincerely, Chris Reed

Science News Update. World Book Science Year 2006

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Technical Asistance: C. Frizzell; and M.Pololos, D.Verrillo and K.Papoulias at EMSB
Copyright 2006


A violation of sig figs!!