Specification Product Name ERIOCHROME BLACK T Synonyms 3-Hydroxy-4-[(1-hydroxy-2-naphthalenyl) azo]-7-nitro-1-naphthalenesulfonic Acid, Monosodium Salt; Mordant Black 11 CAS NO. 1787-61-7 Chemical Formula C20H12N3NaO7S Formula Weight 461.38 Appearance Black Crystalline Powder Structure     Tests    Limits Solubility 0.1% (dist. Water) - Red Solution Absorptivity 1% / 1cm, at (pH 10.0 Ammonia Buffer + 2ml 0.05 M.E.D.T.A. Solution) at λ max.623.0 nm - 464 Loss on drying at 110°C (1hr) - 0.89%         REVISED: 1-1-2012