Thymol blue, or thymolsulfonephthalein, is a crystalline powder that appears brownish-green or reddish-brown. It switches from red to yellow at pH 1.2–2.8 and yellow to blue at pH 8.0–9.6, with distinct structures at different pH levels.
CAS No.: 76-61-9
Synonyms:Thymolsulfonephthalein; Thymolsulfophthalein; Sodium thymol blue; Azul Timol; Timolo blu; Thymol Bleu; Thymolblau
| Physical Properties | |
| Chemical formula | C27H30O5S |
| IUPAC Name | 3,3-Bis[4-hydroxy-2-methyl-5-(propan-2-yl)phenyl]-2,1λ6-benzoxathiole-1,1(3H)-dione |
| Molecular weight | 466.59 g/mol |
| Solubility | alcohol & dilute alkali |
| Insoluble | Water |
| Flash point | 36°C |
| Density | 0.979 g/cm3 |
| λmax | 594 nm, 376 nm, 544 nm, 430 nm |
| Chemical Properties | |
| Colour | Brownish-green or reddish-brown |
| State | Crystalline powder |
| Melting point | 221-224 °C |
| Specific Gravity | >1 g/mL at 20°C |
| Absorbance peak | 593 nm |
| Pictograms : |   |
| Hazard Statements : | H225: Highly Flammable liquid and vapor |
| Precautionary statements : | P210: Keep away from heat, sparks, open flames, and hot surfaces. No smoking |
Thymol blue, or thymolsulfonephthalein, is a crystalline powder that appears brownish-green or reddish-brown. It switches from red to yellow at pH 1.2–2.8 and yellow to blue at pH 8.0–9.6, with distinct structures at different pH levels.
CAS No.: 76-61-9
Synonyms:Thymolsulfonephthalein; Thymolsulfophthalein; Sodium thymol blue; Azul Timol; Timolo blu; Thymol Bleu; Thymolblau
| Physical Properties | |
| Chemical formula | C27H30O5S |
| IUPAC Name | 3,3-Bis[4-hydroxy-2-methyl-5-(propan-2-yl)phenyl]-2,1λ6-benzoxathiole-1,1(3H)-dione |
| Molecular weight | 466.59 g/mol |
| Solubility | alcohol & dilute alkali |
| Insoluble | Water |
| Flash point | 36°C |
| Density | 0.979 g/cm3 |
| λmax | 594 nm, 376 nm, 544 nm, 430 nm |
| Chemical Properties | |
| Colour | Brownish-green or reddish-brown |
| State | Crystalline powder |
| Melting point | 221-224 °C |
| Specific Gravity | >1 g/mL at 20°C |
| Absorbance peak | 593 nm |
| Pictograms : | |
| Hazard Statements : | H225: Highly Flammable liquid and vapor |
| Precautionary statements : | P210: Keep away from heat, sparks, open flames, and hot surfaces. No smoking |
To make a Thymol Blue indicator solution, dissolve Thymol Blue powder in alcohol or dilute alkali. For a typical solution, use 0.04% Thymol Blue in ethanol or a dilute sodium hydroxide solution.
Thymol Blue works as a pH indicator by changing color based on the acidity or alkalinity of a solution. It transitions from red to yellow at pH 1.2–2.8 and yellow to blue at pH 8.0–9.6.
Thymol blue changes color because it acts as a diprotic acid with three different forms, each having a distinct color.
The thymol test, also known as the thymol turbidity test, is used to analyze liver function. It evaluates the amount of certain proteins in the blood that can become abnormal due to liver disease, providing insight into liver damage or dysfunction.
Yes, thymol is known for its antifungal properties. It is a natural compound found in thyme oil and has been shown to inhibit the growth of various fungi.
