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

METHYL RED FREE ACID ACS

Synonyms:				2-[4-(Dimethylamino)phenylazo]benzoic acid;
					C.I. 13020; Acid Red 2

CAS No:					493-52-7

Chemical Formula:				C15H15N3O2

Formula Weight:				269.30

Description:					Red to Purple to Maroon crystalline powder

Melting Range:				179 - 182 deg. C

Loss on drying at 110			< 5% 
deg. C (1 hour):					

Absorptivity 1%, 1cm			To pass test
(pH 6.2) at lambda max 430 nm		> 700
 (pH 4.2) at lambda max 527 nm		> 1350

Clarity of alcohol Solution:		Passes test

Visual Transition Interval	:		From pH 4.2 (pink) 
To     pH 6.2 (yellow)

Effective:10/24/19