1-NAPHTHOLPHTHALEIN excellent quality manufacturer, exporter and supplier. 1-Naphtholphthalein (C28H18O4) is a pH indicator with a visual transition from colorless/reddish to greenish blue at pH 7.3 – 8.7.
As indicator in 0.1% or 0.04% solution in alcohol. pH 7.3 colorless to reddish; 8.7 greenish to blue. Particularly adapted for weak acids in strong alcoholic solution.
pH 7.1 - pH 8.3 pink brownish - blue
Storage of liquid indicator : storage temp. Store below +30°C.solubility Solubility Practically insoluble in water; soluble in ethanol