The peroxomonosulfate ion, SO2−
5, is a sulfur oxoanion. It is sometimes referred to as the persulfate ion, but this term also refers to the peroxydisulfate ion, S
2O2−
8.
Due to its non-toxic nature, it requires only simple handling procedures. Its IUPAC name is O-sulfonoperoxoatooxidanidolate.