THYMOL BLUE SODIUM SALT WATER SOLUBLE Water-soluble thymol blue is called thymol blue sodium salt soluble in water, be dissolved in diluted alkaline and be 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 Indicator Solution: Dissolve 0.1 g of thymol blue in 2.15 ml of 0.1 M sodium hydroxide and 20 ml of ethanol (95 percent). After the solution is effected, add sufficient water to produce 100 ml.