Sulfanilic acid standard for elemental analysis for analysis. CAS 121-57-3, EC Number 204-482-5, chemical formula NH₂C₆H₄SO₃H.

Identity (IR-spectrum)conformsC content (mean value fivefold determination)41.3 - 41.8 %H content (mean value fivefold determination)3.9 - 4.3 %N-content (mean value fivefold determination)7.7 - 8.3 %O content (mean value fivefold determination)27.5 - 28.5 %S content (mean value fivefold determination)18.2 - 18.8 %Water (according to Karl Fischer)≤ 0.5 %Suitable for determination of C,H,N,O,S.