CAS: 596-01-0
Molecular Formula: C28H18O4
Molecular Weight: 418.44
EINECS: 209-875-5
Synonyms: 3,3-bis(4-hydroxynaphthalen-1-yl)-1,3-dihydro-2-benzofuran-1-one; alpha-Naphtholphthalein, indicator, pure 5GR; 3,3-Bis(4-hydroxynaphthalen-1-yl)isobenzofuran-1(3H)-one; 1-NAPHTHOLPHTHALEIN INDICATOR PH 7,1 – 8; 1-NAPHTHOLPHTHALEIN
The impurities in alpha Nathophthalein are mostly light red in color, which changes from light red to blue-green at pH 7.3-8.7.
| Item | Specification |
| Boiling point | 496.21°C (rough estimate) |
| Density | 1.1532 (rough estimate) |
| Melting point | 238-240 °C(lit.) |
| pKa | 8.0, 8.2, 8.5(at 25℃) |
| resistivity | 1.6400 (estimate) |
| Storage conditions | Store below +30°C. |
Alpha Nephthophyllein is used as an acid-base indicator. It is colorless to orange yellow at a pH of around 6.7 and changes from orange yellow to blue at a pH of around 7.9. Impurities in commercially available products often appear as a light red color, which changes from light red to blue-green at a pH of 7.3-8.7.
Usually packed in 25kg/drum,and also can be do customized package.
