Thymol blue
| Names | |
|---|---|
| IUPAC name
3,3-Bis[4-hydroxy-2-methyl-5-(propan-2-yl)phenyl]-2,1λ6-benzoxathiole-1,1(3H)-dione
| |
| Other names
α-Hydroxy-α,α-bis(5-hydroxycarvacryl)-o-toluenesulfonic acid γ-sultone
Thymolsulfonephthalein | |
| Properties | |
| C27H30O5S | |
| Molar mass | 466.59 g/mol |
| Appearance | Brownish-green crystalline powder |
| Density | 0.979 g/cm3 |
| Melting point | 221–224 °C (430–435 °F; 494–497 K) |
| Boiling point | Decomposes |
| 0.011 g/100 ml (25 °C) | |
| Solubility | Soluble in acetic acid, aniline, ethanol Sparingly soluble in acetone, benzene, toluene |
| Vapor pressure | ~0 mmHg |
| Hazards | |
| Safety data sheet | Sigma-Aldrich |
| Related compounds | |
| Related compounds
|
Bromothymol blue |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Thymol blue, also called thymolsulfonephthalein, is an organic chemical compound, used as a pH indicator.
Contents
Properties
Chemical
It transitions from red to yellow at pH 1.2–2.8 and from yellow to blue at pH 8.0–9.6.
Physical
Thymol blue is a brownish-green or reddish-brown crystalline powder. It is practically insoluble in water but soluble in alcohol, aniline as well as dilute alkali solutions.
Availability
Can be bought from chemical suppliers.
Preparation
Thymol blue can be prepared by reacting saccharin with thymol.
Projects
- Make universal indicator
Handling
Safety
Thymol blue doesn't appear to be harmful, though there is little data regarding its toxicity.
Storage
In closed airtight containers.
Disposal
No special disposal is require. May be diluted and poured down the drain or dumped in trash.
Alternatively, it may be destroyed with a strong oxidizing solution, under strong UV light.
