The term persulfate (sometimes known as peroxysulfate or peroxodisulfate) refers to ions or compounds containing the anions SO2−5 or S2O2−8. The anion SO2−5 contains one peroxide group per sulfur center, whereas in S2O2−8, the peroxide group bridges the sulfur atoms. In both cases, sulfur adopts the normal tetrahedral geometry typical for the S(VI) oxidation state. These salts are strong oxidizers. The term persulfate (sometimes known as peroxysulfate or peroxodisulfate) refers to ions or compounds containing the anions SO2−5 or S2O2−8. The anion SO2−5 contains one peroxide group per sulfur center, whereas in S2O2−8, the peroxide group bridges the sulfur atoms. In both cases, sulfur adopts the normal tetrahedral geometry typical for the S(VI) oxidation state. These salts are strong oxidizers.