Phenolphthalein

Molecular formula: C20H14O4

Melting point: 262.5 ° C

Density: 1.227 g/cm after (32 ° C)

Boiling point: 548.7 ℃ at 760 mmHg

Vapor pressure: 7.12 e-13 mmHg at 25 ℃

Solubility: < 0.1g / 100ml

Oil-water distribution coefficient: log Kow = 2.41

Dissociation constant: pKa = 9.7 (25 ℃)

Refractive index: 1.57 (7.9 C)

Stability: stability. Incompatible with strong oxidizing agents and bases.

Storage conditions: keep sealed in a cool, dry and windy area away from incompatible substances.

Phenolphthalein is colorless in acidic and neutral solutions, purplish red in alkaline solutions, orange in extremely acidic solutions, and colorless in extremely alkaline solutions.

When heated to decomposition, it gives off pungent and irritating fumes.