Naphthalenesulfonic acid, 2-hydroxy-1-[[2-methyl-4-[(2-methylphenyl)azo]phenyl]azo]-, monosodium salt

2-Methyl-4-(o-tolyldiazenyl)benzenamine diazo, and 7-Hydroxynaphthalene-1-sulfonic acid (0.5 Moore) and 6-Hydroxynaphthalene-2-sulfonic acid (0.5 Moore) coupled.

red. Slightly soluble in water, soluble in ethanol right amount to red. The strong sulfuric acid is a deep in the red, After dilution into a reddish orange. In water solution to join strong hydrochloric acid for orange red brown; Add thick sodium hydroxide solution for orange red brown.