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Molekula

Molekula

Tropaeolin O

SKU 61804883 CAS 547-57-9 C12H10N2O5S.Na MW 316.27 In stock Bulk quantities on request

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.

Expect a response within hours Speak to a chemist: +44 (0) 3302 000333

Example image for illustration only. Other packaging and pack sizes are available.

Pricing & pack sizes

Pack sizes & pricing

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.

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  • 25 g — $96.90 per pack
  • 100 g — $158.60 per pack

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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

Safety Data Sheets (SDS)

Available in English.

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?

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