Cresol Red
Cresol Red
CAS: 1733-12-6
Molecular Formula: C21H18O5S
Cresol Red - Names and Identifiers
| Name | Cresol Red |
| Synonyms | Cresol Red o-Cresol Red o-Cresolsulfonphthalein o-Cresolsulphonephthalein Cresol Red,pure,Indicator grade o-Cresol Red p.a. (green powder) 3,3-Bis(3-methyl-4-hydroxyphenyl)-3H-2,1-benzoxathiole 1,1-dioxide Phenol, 4,4-(1,1-dioxido-3H-2,1-benzoxathiol-3-ylidene)bis2-methyl- 4,4'-(1,1-dioxido-3H-2,1-benzoxathiole-3,3-diyl)bis(2-methylphenol) 2-[(Z)-(4-hydroxy-3-methylphenyl)(3-methyl-4-oxocyclohexa-2,5-dien-1-ylidene)methyl]benzenesulfonic acid |
| CAS | 1733-12-6 |
| EINECS | 217-064-2 |
| InChI | InChI=1/C21H18O5S/c1-13-11-15(7-9-18(13)22)21(16-8-10-19(23)14(2)12-16)17-5-3-4-6-20(17)27(24,25)26/h3-12,22H,1-2H3,(H,24,25,26)/b21-16- |
| InChIKey | ASMGMVUGPNODGX-UHFFFAOYSA-N |
Cresol Red - Physico-chemical Properties
| Molecular Formula | C21H18O5S |
| Molar Mass | 382.43 |
| Density | 0.998 g/cm3 |
| Melting Point | 290 °C |
| Boling Point | 479.59°C (rough estimate) |
| Water Solubility | soluble |
| Solubility | Solubility Sparingly soluble in water; soluble in ethanol |
| Appearance | reddish brown crystal |
| Color | Dark green or brown-red |
| Maximum wavelength(λmax) | ['570nm, 367nm, 432nm'] |
| Merck | 14,2578 |
| BRN | 343399 |
| pKa | 1.0(at 25℃) |
| PH | 7.2～8.8 |
| Storage Condition | Store at +5°C to +30°C. |
| Sensitive | Easily absorbing moisture |
| Refractive Index | 1.5300 (estimate) |
| MDL | MFCD00005878 |
| Physical and Chemical Properties | Crystals with a green luster, red-brown powder after grinding. Soluble in alcohol and dilute sodium hydroxide solution, slightly soluble in water. |
| Use | Acid-base indicator. |
Cresol Red - Risk and Safety
| Risk Codes | R36/37/38 - Irritating to eyes, respiratory system and skin. R20/21/22 - Harmful by inhalation, in contact with skin and if swallowed. R11 - Highly Flammable |
| Safety Description | S24/25 - Avoid contact with skin and eyes. S36 - Wear suitable protective clothing. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S16 - Keep away from sources of ignition. |
| UN IDs | UN1170 - class 3 - PG 3 - Ethanol, solution |
| WGK Germany | 3 |
| TSCA | Yes |
| HS Code | 29349990 |
| Toxicity | A potent lacrimator which is chemically stable and retains its irritancy in water and so can be used in liquid jets in personnel control. In addition to lacrimation, it causes eye pain, blepharospasm, eyelid swelling, irritation of the conjunctiva, a rise in intraocular pressure, and erythema of the skin. Because it can be used in water, its use is less affected by changes in climatic conditions. It is a more potent lacrimator than CS but it is less potent in lethality than CS. |
Cresol Red - Nature
Open Data Verified Data
red-brown or dark-red crystalline powder. mp is about 290 °c (decomposition). Soluble in dilute acid (yellow), dilute hydroxide alkali solution (purple), soluble in ethanol, water. PH 0.2~1.8 (from red to yellow);7.O ~ 8.0 (from yellow to purple).
Last Update：2024-01-02 23:10:35
Cresol Red - Preparation Method
Open Data Verified Data
The ortho-sulfobenzoic acid was prepared by mixing and heating the ortho-cresol.
Last Update：2022-01-01 09:26:02
Cresol Red - Introduction
Easily soluble in alcohol and dilute hydroxide alkali solution, slightly soluble in water, its 0-1% alcohol solution or 0-04% sodium salt aqueous solution is used as an indicator.
Last Update：2022-10-16 17:14:25
Cresol Red - Use
Open Data Verified Data
acid-base indicator.
Last Update：2022-01-01 09:26:02
Cresol Red - Reference Information
| pH indicator color change ph range | 7.2(YELLOW)-8.8(PURPLISH RED) |
| main applications | Display device, optical sensors, combustion gas detection system, inks, correction fluid, diapers, toothpaste, identifying fresh and stale rice, food storage, determine glucose in dialysis solution, monitor metabolic activity of microorganisms, detect bacterialinfection, psychoactive drugs, dental impression material |
| EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
| use | acid-base reminder. Use 20% ethanol to prepare 0.1% solution or 0.04% aqueous solution (0.04g of the product is dissolved in 1.05ml of 0.1MNaOH solution), and then dilute to 100ml. pH color change range: 7.2 (yellow)-8.8 (purple red);2.0 (red)-3.0 (amber). Acid-base indicator. |
| production method | benzesulfonic anhydride, o-cresol and anhydrous zinc chloride are mixed, stirred and heated, condensed and reacted at 115-120 ℃ for about 7 hours, and the remaining o-cresol is driven by water vapor. Filter, dissolve the filter cake with hot sodium carbonate aqueous solution, filter, add 1:1 hydrochloric acid to the clear filtrate to neutralize, and stir vigorously. Filter out the crystals, wash with a small amount of water, and dry to obtain the finished product. If necessary, it can be recrystallized and purified with glacial acetic acid. |
Last Update：2024-04-10 22:29:15
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Product Name: Cresol Red Visit Supplier Webpage Request for quotationCAS: 1733-12-6
Tel: 18301782025
Email: 3008007409@qq.com
Mobile: 18021002903
QQ: 3008007409
Wechat: 18301782025
Product Name: Cresol Red Request for quotation
CAS: 1733-12-6
Tel: 13998106873
Email: 297303255@qq.com
Mobile: 13998106873
QQ: 297303255Send QQ message
CAS: 1733-12-6
Tel: 13998106873
Email: 297303255@qq.com
Mobile: 13998106873
QQ: 297303255
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