Molekula
Chlorophenol Red
Supplying 4,500+ customers in over 80 countries
ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 2000 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need
Chlorophenol Red is a synthetic pH indicator dye, primarily used in analytical chemistry for titrations and colorimetric pH measurements in the range of about 4.8 to 6.7. It appears yellow in acidic conditions and red in alkaline environments, making it useful for monitoring pH shifts in the weakly acidic region in laboratory settings. This chemical has a CAS number of 4430-20-0, with the molecular formula C19H12Cl2O5S and a molecular weight of 423.2666. It is stored at ambient conditions and carries a signal word of "Warning" for safety classification. Molekula supplies Chlorophenol Red from research to bulk quantities with full documentation and ISO 9001:2015 traceability.
Example image for illustration only. Other packaging and pack sizes are available.
Pricing & pack sizes
These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.
Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.
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5 g — £35.80 per pack ex VAT · £42.96 inc. VAT
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Tell us how much you need and when — drums, IBCs, sacks or a one-off bulk lot. We'll manufacture or source it and come back with a price.
Prices exclude VAT/sales tax and shipping.
Specifications
| Property | Value |
|---|---|
| Appearance | Crystalline powder or chunks |
| Loss on Drying | max 7.00% |
| Assay | min 93.00% |
| Specific absorption | min 1550.0 |
| Solubility at 0.1% (95% Ethanol) | Clear solution |
| Wavelength of maximum absorption (0.1N NaOH) | 573.0 - 579.0nm |
| pH Transition - Colour Change | pH 4.8 (Brownish Yellow) - pH 6.4 (Violet) |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Neutral |
Literature values
Published physical properties of the substance, not batch specifications.
| Property | Value |
|---|---|
| Melting Point | 261 - 262 °C |
Source: PubChem CID 20486 (Human Metabolome Database (HMDB))
Identification
| Property | Value |
|---|---|
| SKU | 28830424 |
| CAS Number | 4430-20-0 |
| IUPAC Name | 2-chloro-4-[3-(3-chloro-4-hydroxyphenyl)-1,1-dioxo-2,1lambda6-benzoxathiol-3-yl]phenol |
| Molecular Formula | C19H12Cl2O5S |
| Molecular Weight | 423.2666 |
| Exact Mass | 421.9783 |
| SMILES | C1=CC=C2C(=C1)C(OS2(=O)=O)(C3=CC(=C(C=C3)O)Cl)C4=CC(=C(C=C4)O)Cl |
| InChIKey | WWAABJGNHFGXSJ-UHFFFAOYSA-N |
| InChI | InChI=1S/C19H12Cl2O5S/c20-14-9-11(5-7-16(14)22)19(12-6-8-17(23)15(21)10-12)13-3-1-2-4-18(13)27(24,25)26-19/h1-10,22-23H |
| PubChem CID | 20486 |
| REACH Code | Y113 |
| TSCA Listed | Yes |
| HTS Code | 29349990 |
| Tariff Code | 2934999090 |
Safety & GHS
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Health Hazard
GHS07
Hazard statements
- H315 Causes skin irritation
- H319 Causes serious eye irritation
- H335 May cause respiratory irritation
Precautionary statements
- P261 Avoid breathing dust/fume/gas/mist/vapours/spray
- P280 Wear protective gloves/protective clothing/eye protection/face protection
- P305+351+338 IF IN EYES: Rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing
- P308+313 IF exposed or concerned: Get medical advice/attention
Documents
Safety Data Sheets (SDS)
Available in English, French, German, Italian, Russian, Spanish.
Certificate of Analysis (CoA) by batch
Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.
Synonyms
- 3,3-bis(3-chloro-4-hydroxyphenyl)-3H-2,1$l^(6)-benzoxathiole-1,1-dione
- 3,3-Bis(3-chloro-4-hydroxyphenyl)-3H-benzo[c][1,2]oxathiole 1,1-dioxide
- 3',3'-Dichlorophenolsulfonaphthalein
- 3',3''-Dichlorophenolsulfonphthalein
- Chlorophenol red indicator
- Chlorphenol Red
- Chlorphenolsulfonphthalein
- Dichlorophenolsulfonephthalein
- Phenol, 4,4'-(1,1-dioxido-3H-2,1-benzoxathiol-3-ylidene)bis[2-chloro-
- Phenol, 4,4'-(3H-2,1-benzoxathiol-3-ylidene)bis[2-chloro-, S,S-dioxide
Frequently asked questions
What is Chlorophenol Red primarily used for?
Chlorophenol Red is commonly used as a pH indicator in analytical chemistry, particularly in the pH range of about 4.8–6.7, and as a reagent in biochemical assays.
What is the chemical formula and molecular weight of Chlorophenol Red?
The chemical formula is C19H12Cl2O5S and the molecular weight is 423.27 g/mol.
How should Chlorophenol Red be stored?
Store Chlorophenol Red at ambient temperature in a tightly sealed container, away from direct light and moisture.
What grades or purities of Chlorophenol Red does Molekula supply?
Molekula supplies Chlorophenol Red in analytical and reagent-grade purity, suitable for laboratory and industrial applications.
Can Molekula supply Chlorophenol Red in bulk quantities?
Yes, Molekula can provide Chlorophenol Red in bulk, with quantities tailored to customer requirements—please contact us for pricing and availability.
What documentation comes with an order of Chlorophenol Red?
Each order includes a Certificate of Analysis (CoA), Material Safety Data Sheet (MSDS), and a product specification sheet.
Ready to order or need a custom pack?
Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.