1-Naphtholphthalein (pH Indicator)
1-naphtholphthalein
Product Code. |
01782A |
Grade |
|
Purity |
CAS No. |
596-01-0 | |
Molecular Formula |
C28H18O4 |
Molecular Weight |
418.45 |
H.S.Code |
3204.90000 |
Shelf Life |
60 Months |
Physical Properties
| Physical state at 20 °C |
Solid |
Colour |
Black powder |
Odour |
Characteristic odour |
| Melting point/ Freezing point [°C] |
238 - 240 °C |
Vapour density |
14.44 |
Solubility in water [% weight] |
Insoluble in water |
| Partition coefficient Log Pow octanol / water at 20°C |
5.41 |
Packaging
Specification
| Appearance | Light Pink to Beige to Red-Brown Powder |
| Loss on drying (at 105°C) | Max 5% |
| pH transition range (7.1 - 8.3) | Brownish pink to blue |
| Absorption maxima (Buffer pH 7.1) | 471 - 485 nm |
| Absorption maxima (buffer pH 8.3) | 649 - 654 nm |
Safety Information and Hazard Symbols
Symbol: GHS07
Signal Word: Warning
Hazardous Statement: H315-H319-H335
Precaution Statement: P261-P305 + P351 + P338