Molekula
Tropaeolin O
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
Tropaeolin O is a sodium salt of a synthetic azo dye used primarily as a pH indicator and in biochemical assays. It appears as a red crystalline powder and is soluble in water. CAS: 547-57-9, Molecular Formula: C12H10N2O5S.Na, Molecular Weight: 316.27 g/mol. Stable at ambient temperature. Molekula supplies Tropaeolin O 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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25 g — £51.00 per pack ex VAT · £61.20 inc. VAT
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100 g — £83.50 per pack ex VAT · £100.20 inc. VAT
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 | Orange - brown powder |
| Solubility | Clear, red brown solution |
| Lambda max | 487nm (in 0.1/v sodium hydroxide) |
| Visual Transition Interval | From pH 11.0 (yellow) to pH 12.7 (red) |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Acidity | Base |
Identification
| Property | Value |
|---|---|
| SKU | 61804883 |
| CAS Number | 547-57-9 |
| IUPAC Name | sodium 4-[(2,4-dihydroxyphenyl)diazenyl]benzenesulfonate |
| EC Number | 208-924-8 |
| Molecular Formula | C12H10N2O5S.Na |
| Molecular Weight | 316.27 |
| Exact Mass | 316.013 |
| SMILES | C1=CC(=CC=C1N=NC2=C(C=C(C=C2)O)O)S(=O)(=O)[O-].[Na+] |
| InChIKey | COEZWFYORILMOM-UHFFFAOYSA-M |
| InChI | InChI=1S/C12H10N2O5S.Na/c15-9-3-6-11(12(16)7-9)14-13-8-1-4-10(5-2-8)20(17,18)19;/h1-7,15-16H,(H,17,18,19);/q;+1/p-1 |
| PubChem CID | 2728027 |
| REACH Code | Y113 |
| TSCA Listed | Yes |
| HTS Code | 2927.00.30.00 |
| Tariff Code | 2927000090 |
Safety & GHS
Precautionary statements
- P264 Wash thoroughly after handling
- P280 Wear protective gloves/protective clothing/eye protection/face protection
Documents
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
- ACID ORANGE 6
- C.I. Acid Orange 6
- Chrysoine
- Chrysoine Extra
- Chrysoine S
- Chrysonine S
- Resorcin yellow
- Resorcinol yellow
- Tropaeoline
- Tropaeoline O
Frequently asked questions
What is Tropaeolin O used for?
Tropaeolin O is primarily used as a pH indicator in analytical chemistry and as a dye in biochemical assays.
What is the chemical formula and molecular weight of Tropaeolin O?
The formula is C12H10N2O5S.Na with a molecular weight of 316.27 g/mol.
How should Tropaeolin O be stored?
It should be stored at ambient temperature, protected from moisture and light.
What grade of Tropaeolin O is available?
Molekula supplies Tropaeolin O in analytical grade.
Can Molekula supply Tropaeolin O in bulk?
Yes, Molekula can supply Tropaeolin O in bulk quantities upon request.
What documentation comes with a Tropaeolin O order?
Each order includes a Certificate of Analysis (CoA) and safety data sheet (SDS).
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.