When the molar ratio of SbF5 to HF is 0.2: 1, the acidity is more than 9 times that of 100% sulfuric acid, and it is enhanced with the increase of the ratio of SbF5.
In terms of composition, superacid is a solution composed of two or more fluorine-containing compounds. Their acidity is unbelievable. For example, when hydrofluoric acid and lead pentafluoride are mixed in the molar ratio of 1: 0.3, their acidity is 1 100 million times that of concentrated sulfuric acid. When mixed according to 1: 1, its acidity is 1 100 million times that of concentrated sulfuric acid. So aqua regia can only be "dwarfed" in front of them.
Due to the surprisingly strong acidity and corrosiveness of superacid, some chemical reactions that were extremely difficult or impossible to realize in the past can also proceed smoothly under the condition of superacid. For example, n-butane, under the action of super acid, can break carbon-hydrogen bonds to generate hydrogen, can also break carbon bonds to generate methane, and can also isomerize to generate isobutane, which ordinary acids can't do.