S P E C I F I C A T I O N S

XYLENOL BLUE INDICATOR GRADE

Synonyms:		4,4’-(3H-2,1-Benzoxathiol-3-ylidene)bis[2,5-dimethylphenol] 5,5-				dioxide; p-Xylenolsulfonephthalein; 1,4-dimethyl-5-						hydroxybenzenesulfonephthalein

CAS No.:				125-31-5

Molecular Formula:		C23H22O5S

Formula Weight:			410.49  

Appearance:				Dark-brown to purple powder 
      
Melting Point:			212 °C (dec.)

Loss on drying at 110 °C(1hr):  	

Dye content:				~90%

Visual Transition Interval:	From pH 1.2 (red)
 (acid)					To     pH 2.8 (yellow) 

Visual Transition Interval:	From pH 8.0 (yellow)
 (alkaline)				To     pH 9.8 (violet)  

Effective Date: 12/15/08