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Molekula

Molekula

Methyl Orange

SKU 42196193 CAS 547-58-0 C14H14N3NaO3S MW 327.33 In stock (5+ packs) — same-day dispatch 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

Methyl Orange is a synthetic azo dye primarily used as a pH indicator in laboratories and industrial processes, changing color from red to yellow-orange around pH 3.1–4.4. It is also employed in titrations and as a dye for textiles, paper, and cosmetics. This chemical has a CAS number of 547-58-0, a molecular formula of C14H14N3NaO3S, and a molecular weight of 327.33 g/mol. It should be stored at ambient conditions and handled with caution, as it carries a "Danger" signal word. Molekula supplies Methyl Orange 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.

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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.

Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.

  • 25 g — £30.90 per pack ex VAT · £37.08 inc. VAT
  • 100 g — £45.00 per pack ex VAT · £54.00 inc. VAT
  • 500 g — £108.80 per pack ex VAT · £130.56 inc. VAT

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Specifications

Property Value
Appearance Orange/ yellow powder
pH 3.0 - 4.4
Loss on Drying ≤ 5.0%
Dye Content ≥ 95.0%

Storage & handling

Property Value
Storage Temperature Ambient
Transport Class 6.1
Packing Group III
Acidity Acid

Identification

Property Value
SKU 42196193
CAS Number 547-58-0
IUPAC Name sodium 4-[[4-(dimethylamino)phenyl]diazenyl]benzenesulfonate
EC Number 208-925-3
Molecular Formula C14H14N3NaO3S
Molecular Weight 327.33
Exact Mass 327.0654
SMILES CN(C)C1=CC=C(C=C1)N=NC2=CC=C(C=C2)S(=O)(=O)[O-].[Na+]
InChIKey STZCRXQWRGQSJD-UHFFFAOYSA-M
InChI InChI=1S/C14H15N3O3S.Na/c1-17(2)13-7-3-11(4-8-13)15-16-12-5-9-14(10-6-12)21(18,19)20;/h3-10H,1-2H3,(H,18,19,20);/q;+1/p-1
PubChem CID 23673835
UN Number UN3143
REACH Code Y110
TSCA Listed Yes
HTS Code 29270030
Tariff Code 2927000090

Safety & GHS

Danger
  • GHS pictogram — Toxic Toxic GHS06

Hazard statements

  • H301 Toxic if swallowed

Precautionary statements

  • P280 Wear protective gloves/protective clothing/eye protection/face protection
  • P301+310 IF SWALLOWED: Immediately call a POISON CENTER or doctor/physician
  • P302+352 IF ON SKIN: Wash with soap and water
  • P304+341 IF INHALED: If breathing is difficult, remove victim to fresh air and keep at rest in a position comfortable for breathing
  • P305+351+338 IF IN EYES: Rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing
  • P331 Do NOT induce vomiting

Documents

Safety Data Sheets (SDS)

Available in English, French, German, Italian, 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

  • Acid Orange 52
  • C.I. 13025
  • C.I. Acid Orange 52
  • Eniamethyl Orange
  • Gold Orange
  • Helianthine
  • Helianthine B
  • Methyl Orange B
  • Orange III
  • Tropaeolin D

Frequently asked questions

What is Methyl Orange primarily used for?

Methyl Orange is commonly used as a pH indicator in acid-base titrations, typically changing color from red to yellow-orange around pH 3.1–4.4.

What is the chemical formula and molecular weight of Methyl Orange?

The chemical formula is **C₁₄H₁₄N₃NaO₃S**, and the molecular weight is **327.33 g/mol**.

How should Methyl Orange be stored?

Store Methyl Orange at **ambient temperature** in a tightly sealed container, away from direct sunlight and moisture.

What grades or purities of Methyl Orange does Molekula supply?

Molekula supplies **analytical grade** Methyl Orange, suitable for laboratory and industrial applications requiring consistent performance.

Can Molekula supply Methyl Orange in bulk quantities?

Yes, Molekula can provide Methyl Orange in bulk, with quantities and packaging tailored to your specific requirements.

What documentation comes with an order of Methyl Orange?

Each order includes a **Certificate of Analysis (CoA)**, **Material Safety Data Sheet (MSDS)**, and **batch-specific documentation** for traceability.

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