Why does thymol turn blue?
Answer Expert Verified Thymol blue shows red color at below pH than 1.2 and shows yellow color at the pH between 2.8 and 8.0. For the pH above 9.6, thymol blue shows blue color. Hence, the thymol blue has 2 pH ranges as 1.2 – 2.8 and 8.0 – 9.6. Since, pH = 11 is above the pH = 9.6, thymol blue shows blue color.
What color does thymol blue change to?
yellow
Thymol blue (thymolsulfonephthalein) is a brownish-green or reddish-brown crystalline powder that is used as a pH indicator. It is insoluble in water but soluble in alcohol and dilute alkali solutions. It transitions from red to yellow at pH 1.2–2.8 and from yellow to blue at pH 8.0–9.6.
What colour is thymol blue in acid?
| Indicator | pH Range | color in acid form |
|---|---|---|
| Thymol Blue | 1.2 – 2.8 | red |
| Methyl Orange | 3.1 – 4.4 | red |
| Methyl Red | 4.2 – 6.3 | red |
| Thymol Blue | 8.0 – 9.6 | yellow |
What is the colour of the acid base indicator thymol blue at each of the following pH values?
| Indicator | pH Range | Alkali |
|---|---|---|
| 28 Phenol red | 6.4-8.4 | red |
| 27 Phenolphthalein | 8.2-10 | red |
| 34 Thymol blue (1st range) | 1.2-2.8 | yellow |
| 34.1 Thymol blue (2nd range) | 8.0-9.6 | blue |
How do you make thymol blue?
Thymol Blue Indicator Solution: Dissolve 0.1 g of thymol blue in 2.15 ml of 0.1 M sodium hydroxide and 20 ml of ethanol (95 percent). After the solution is effected, add sufficient water to produce 100 ml.
Is thymol Diprotic blue?
For example, thymol blue changes from red to yellow in the pH range of 1.2 to 2.8, then from yellow to blue in the pH range of 8.0 to 9.6. What is happening here is that thymol blue acts as a diprotic acid, having three forms each with a different colour.
Why does thymol blue have two color transitions?
Explanation: Thymol blue changes colour at two different pH ranges. The first colour change is from red to yellow at pH 1.2–2.8, and the second is from yellow to blue at pH 8.0 – 9.6. At pH 10, the indicator is past its second colour change, so the solution will be blue .
What is the chemical structure of thymol blue?
C27H30O5S
Thymol blue | C27H30O5S – PubChem.
Is thymol blue A acid or base?
Thymol blue is another weak acid that is used as an indicator. The fully protonated species (abbreviated H2Thy) is red, the monoprotonated species (HThy-) is yellow, and the fully deprotonated species (Thy2-) is blue.
What is the pKa of thymol blue?
1.2 to 2.8
Acid-Base Indicators
| Indicator | pH Range | pKa |
|---|---|---|
| Thymol blue | 1.2 to 2.8 | 1.65 |
| Methyl yellow | 2.9 to 4.0 | 3.3 |
| Methyl orange | 3.1 to 4.4 | 3.4 |
| Bromophenol blue | 3.0 to 4.6 | 3.85 |
What makes saturated copper ( II ) chloride turn green?
Saturated copper(II) chloride in ethanol is green. When water is added, it turns blue. Concentrated hydrochloric acid is added, changing the solution back to green.
What can be used in place of thymol?
(f) The use of 4–5 drops of concentrated formaldehyde solution (40 per cent) may be used as a preservative in place of thymol in solution 4. MSNs are used to load essential oils like carvacrol, cinnamaldehyde, eugenol, and thymol, showing enhancement of antifungal activity against Aspergillus niger.
What is the color of copper in aqueous solution?
The copper ion in the aqueous solution of exists predominantly as [Cu(H 2 O) 6] 2+. This complex ion imparts a characteristic pale blue color to the solution. This complex ion imparts a characteristic pale blue color to the solution.
What is the role of copper ( II ) chloride?
Copper (II) chloride is an inorganic chloride of copper in which the metal is in the +2 oxidation state. It has a role as an EC 5.3.3.5 ( cholestenol Delta-isomerase) inhibitor. It is an inorganic chloride and a copper molecular entity. It contains a copper (2+).