What is "chlorosulfuric acid"

alt. (context inorganic compound English) The strong acid ClSO₂OH obtained from sulfuric acid by the replacement of a hydroxyl group with a chlorine atom; it is used in the preparation of sulfonic acids n. (context inorganic compound English) The strong acid ClSO₂OH obtained from sulfuric acid by the replacement of a hydroxyl group with a chlorine atom; it is used in the preparation of sulfonic acids

Chlorosulfuric acid ( IUPAC name: sulfurochloridic acid) is the inorganic compound with the formula HSOCl. It is also known as chlorosulfonic acid, being the sulfonic acid of chlorine. It is a distillable, colorless liquid which is hygroscopic and a powerful lachrymator.