ODM2 Variable Name Controlled Vocabulary ODM2 Working Group A vocabulary for describing the name of Variables. Sulfate The sulfate or sulphate (see spelling differences) ion is a polyatomic anion with the empirical formula SO2- 4. Sulfate is the spelling recommended by IUPAC, but sulphate is used in British English. Salts, acid derivatives, and peroxides of sulfate are widely used in industry. Sulfates occur widely in everyday life. Sulfates are salts of sulfuric acid and many are prepared from that acid. Wikipedia https://en.wikipedia.org/wiki/Sulfate Added to support Critical Zone Observatory (CZO) data use cases.