77-09-8-Phenolphthaleine-Indicator-Powder-50 Phenolphthalein (Indicator) Powder Synonym: 3,3-Bis(4-hydroxyphenyl)-1(3H)-isobenzofuranone CAS Number: 77-09-8 Linear Formula: C20H14O4 Molecular Weight: 318.32 Physical Form: Powder Packaging: Plastic Bottle