Molekula
Methyl red hydrochloride
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
Methyl red hydrochloride is a synthetic pH indicator dye used primarily in acid-base titrations, biological staining, and analytical chemistry to detect pH changes between 4.4 and 6.2, shifting from red to yellow. This chemical has a CAS number of 63451-28-5, a molecular formula of (CH3)2NC6H4N=NC6H4CO2H·HCl, and a molecular weight of 305.76 g/mol. It should be stored at ambient conditions and carries a signal word of Danger due to its hazardous nature. Molekula supplies Methyl red hydrochloride 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
Pack sizes & pricing
Pricing on request — packs available from research to bulk quantities.
Need a different quantity or pack?
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 | Dark purple to dark violett crystalline powder |
| Loss on Drying | <10% |
| Solubility (0.1% in 95% ethanol) | Clear solution |
| Absorptivity (E 1% in 1cmcell, pH 4.2 max | lambda max 526.6nm; >1100 |
| Absorptivity (E 1% in 1cmcell, pH 6.2 max | lambda max 431.4nm: >620 |
| Visual Transition Interval | pH 4.2 pink, pH 6.2 yellow |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Neutral |
Identification
| Property | Value |
|---|---|
| SKU | 90034618 |
| CAS Number | 63451-28-5 |
| IUPAC Name | 2-[[4-(dimethylamino)phenyl]diazenyl]benzoic acid;hydrochloride |
| EC Number | 264-190-9 |
| Molecular Formula | (CH3)2NC6H4N=NC6H4CO2H·HCl |
| Molecular Weight | 305.76 |
| Exact Mass | 305.0931 |
| SMILES | CN(C)C1=CC=C(C=C1)N=NC2=CC=CC=C2C(=O)O.Cl |
| InChIKey | ICTWKXAVJAHRMK-UHFFFAOYSA-N |
| InChI | InChI=1S/C15H15N3O2.ClH/c1-18(2)12-9-7-11(8-10-12)16-17-14-6-4-3-5-13(14)15(19)20;/h3-10H,1-2H3,(H,19,20);1H |
| PubChem CID | 113227 |
| REACH Code | Y110 |
| HTS Code | 32129000 |
| Tariff Code | 3212900000 |
Safety & GHS
-
Serious Health Hazard
GHS08
Hazard statements
- H351 Suspected of causing cancer
Precautionary statements
- P261 Avoid breathing dust/fume/gas/mist/vapours/spray
- P280 Wear protective gloves/protective clothing/eye protection/face protection
- P309+311 IF exposed or you feel unwell: Call a POISON CENTER or doctor/physician
Documents
Safety Data Sheets (SDS)
Available in English, English (US), French, German, Italian, Portuguese, 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
- 2-((4-(Dimethylamino)phenyl)azo)benzoic acid monohydrochloride
- 2-[[4-(dimethylamino)phenyl]diazenyl]benzoic acid;hydrochloride
- 2-[4-(dimethylamino)phenyl]azobenzoic acid;hydrochloride
- 2-{[4-(dimethylamino)phenyl]diazenyl}benzoic acid, chloride
- 2((4(Dimethylamino)phenyl)azo)benzoic acid
- Benzoic acid, 2-[[4-(dimethylamino)phenyl]azo]-, monohydrochloride
- Benzoic acid, 2-[2-[4-(dimethylamino)phenyl]diazenyl]-, hydrochloride (1:1)
- Benzoic acid, 2((4(dimethylamino)phenyl)azo),
- ICTWKXAVJAHRMK-UHFFFAOYSA-N
- Methyl red hydrochloride ACS grade
Frequently asked questions
What is methyl red hydrochloride commonly used for?
Methyl red hydrochloride is primarily used as a pH indicator in titrations, particularly for detecting endpoints in acid-base titrations (e.g., in the titration of weak bases with strong acids). It is also used in microbiology for differential staining and in some biochemical assays.
What is the chemical formula and molecular weight of methyl red hydrochloride?
The chemical formula is **(CH3)2NC6H4N=NC6H4CO2H·HCl**, and the molecular weight is **305.76 g/mol**.
How should methyl red hydrochloride be stored?
Store methyl red hydrochloride at **ambient temperature** in a tightly sealed container, away from moisture and direct sunlight.
What grades of methyl red hydrochloride does Molekula supply?
Molekula supplies methyl red hydrochloride in **analytical reagent grade** for laboratory applications. Bulk or custom grades may be available upon request.
Can Molekula supply methyl red hydrochloride in bulk quantities?
Yes, Molekula can supply methyl red hydrochloride in **bulk quantities** depending on availability and customer requirements. Please contact us for specific pricing and lead times.
What documentation comes with an order of methyl red hydrochloride?
Each order includes a **Certificate of Analysis (CoA)**, **Material Safety Data Sheet (MSDS)**, and **batch-specific documentation** for traceability. Additional certifications (e.g., ISO, GMP) may be provided upon request.
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.