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.
Thymol blue is another weak acid that is used as an indicator. The fully protonated species (abbreviated H2Thy) is red, the monoprotonated species (HThy-) is yellow, and the fully deprotonated species (Thy2-) is blue.
Thymol blue is used as a pH indicator. It transitions from red to yellow at pH 1.2–2.8 and from yellow to blue at pH 8.0–9.6. It is usually a component of Universal indicator.
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. It transitions from red to yellow at pH 1.2–2.8 and from yellow to blue at pH 8.0–9.6.
THYMOL BLUE INDICATOR AR