Specification Product Name BROMOTHYMOL BLUE Synonyms 3',3"-Dibromothymolsulfonephthalein CAS NO. 76-59-5 Molecular Formula C27H28Br2O5S Formula Weight 624.40 Appearance Beige to light pink to light brown to red powder Structure     Tests    Limits Transition Range - pH 5.8 - pH 7.6 Yellow - Blue Solubility 0.1% (EtOH] - Clear Yellow solution Absorptivity 1%/1cm, (pH 5.8) at λ Max.432.0 nm (pH 7.6) at λ Max.616.0 nm - 260-300 - 470-520 Loss on Drying at110°C (1hr) - <3%         REVISED: 1-1-2012