Fluorosulfuric acid

Fluorosulfuric acid (HSO₃F) is a strong inorganic acid in which fluorine replaces one hydroxyl group of sulfuric acid. It is a colorless, highly corrosive liquid and a useful reagent for generating superacids.

Brønsted–Lowry acid: A species that donates a proton to another species. Fluorosulfuric acid acts as a proton donor in acid–base reactions.
Sulfuric acid: A strong diprotic acid with formula H₂SO₄, consisting of sulfur bonded to four oxygen atoms. Replacing one hydroxyl group of sulfuric acid with fluorine gives fluorosulfuric acid.
Superacid: An acid stronger than pure sulfuric acid under comparable acidity measures. Fluorosulfuric acid is a superacid and can form even stronger acid mixtures.
Triflic acid: A strong sulfonic acid with formula CF₃SO₃H, also called trifluoromethanesulfonic acid. It is a widely used strong acid whose conjugate base differs markedly from fluorosulfate.
Conjugate base: The species formed when an acid donates a proton. Proton loss from fluorosulfuric acid produces the fluorosulfate ion.
Sulfur–fluorine bond: A covalent bond between sulfur and fluorine atoms. The S–F bond distinguishes fluorosulfuric acid from sulfuric acid.
Magic acid: A superacid mixture of fluorosulfuric acid and antimony pentafluoride. Fluorosulfuric acid is a principal component of this exceptionally strong protonating mixture.
Perchloric acid: A strong mineral acid with formula HClO₄. It offers a familiar strong-acid comparison, though its chemistry and hazards differ.
Fluorosulfate: The anion HSO₃F⁻? This is the conjugate base formed when fluorosulfuric acid loses a proton.
Oxyacid: An acid whose molecular structure contains oxygen bonded to a central atom. Fluorosulfuric acid retains an oxygen-rich sulfur framework despite its S–F bond.

Linked from 5 pages

Antimony pentafluorideRelated: Its mixture with SbF₅ produces Magic acid, a distinct superacid system.