METHYL THYMOL BLUE COMPLEXONE : Thymol blue (thymolsulfonephthalein) is a brownish-green or reddish-brown crystalline powder that is used as a pH indicator. It is insoluble in water but soluble in alcohol and dilute alkali solutions.
Methylthymol blue is a Water soluble chelometric indicator. Methylthymol blue MTB is a metal- lochromic indicator which forms metal complexes different in spectral absorption characteristics from the free indicator.