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Molekula

Molekula

Selenium dioxide

SKU 30100275 CAS 7446-08-4 SeO2 MW 110.96 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

Selenium dioxide is a highly reactive inorganic compound composed of selenium and oxygen, primarily used as an oxidizing agent in organic synthesis, dye manufacturing, and as a reagent in chemical analysis. It is also employed in the production of glass and ceramics for its colorant properties, and as a starting material for the preparation of other selenium compounds. This chemical has a CAS number of 7446-08-4, with the molecular formula SeO2 and a molecular weight of 110.96 g/mol. It should be stored at ambient conditions but handled with caution, as it carries a Danger signal word due to its hazardous nature. Molekula supplies selenium dioxide 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.

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 — $70.90 per pack
  • 100 g — $130.20 per pack
  • 500 g — $414.40 per pack

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Prices exclude VAT/sales tax and shipping.

Specifications

Property Value
Appearance White to off-white or Pink powder
Identification Conforms to reference
Assay ≥98%

Storage & handling

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

Literature values

Published physical properties of the substance, not batch specifications.

Property Value
Appearance Lustrous tetragonal needles; yellowish green vapor
Odour Vapor has a pungent sour smell
Melting Point 340 °C under pressure
Boiling Point 315 °C at 760 mmHg (sublimes)
Water Solubility 400 g/L at 20 °C
Solubility (other solvents) Soluble in concentrated sulfuric acid
Vapour Pressure 1.65 kPa at 70 °C

Source: PubChem CID 24007 (HSDB, CAMEO Chemicals, ICSC)

Identification

Property Value
SKU 30100275
CAS Number 7446-08-4
IUPAC Name selenium dioxide
EC Number 231-194-7
Molecular Formula SeO2
Molecular Weight 110.96
Exact Mass 111.9064
SMILES O=[Se]=O
InChIKey JPJALAQPGMAKDF-UHFFFAOYSA-N
InChI InChI=1S/O2Se/c1-3-2
PubChem CID 24007
UN Number UN3283
REACH Code Y110
TSCA Listed Yes
HTS Code 2811.29.2000
Tariff Code 2811299090

Safety & GHS

Danger
  • GHS pictogram — Corrosive Corrosive GHS05
  • GHS pictogram — Toxic Toxic GHS06
  • GHS pictogram — Serious Health Hazard Serious Health Hazard GHS08
  • GHS pictogram — Hazardous to the Environment Hazardous to the Environment GHS09

Hazard statements

  • H300 Fatal if swallowed
  • H314 (sub cat. 1B) Causes severe skin burns and eye damage
  • H331 Toxic if inhaled
  • H372 Causes damage to organs through prolonged or repeated exposure
  • H410 Very toxic to aquatic life with long lasting effects

Precautionary statements

  • P260 Do not breathe dust/fume/gas/mist/vapours/spray
  • P273 Avoid release to the environment
  • 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+312 IF INHALED: Call a POISON CENTER or doctor/physician if you feel unwell

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

  • (oxo-lambda4-selanylidene)oxidane
  • Dioxide, Selenium
  • Oxide, Selenium
  • Selenious anhydride
  • Selenium dioxide dimer
  • Selenium oxide (1:2)
  • Selenium oxide (Se2O4)
  • Selenium oxide (SeO2)
  • Selenium(IV) dioxide (1:2)
  • Selenous acid anhydride

Frequently asked questions

What is selenium dioxide primarily used for?

Selenium dioxide is commonly used as an oxidizing agent in organic synthesis, as a reagent in the production of selenides, and in the manufacturing of glass, ceramics, and pigments.

What is the chemical formula and molecular weight of selenium dioxide?

The chemical formula is SeO₂, and the molecular weight is 110.96 g/mol.

How should selenium dioxide be stored?

Store selenium dioxide in a cool, dry place at ambient temperature, away from incompatible substances like strong oxidizers or reducing agents.

What grades of selenium dioxide does Molekula supply?

Molekula supplies technical and reagent-grade selenium dioxide, depending on your application requirements.

Can Molekula supply selenium dioxide in bulk quantities?

Yes, Molekula can provide selenium dioxide in bulk packaging (e.g., drums or bags) for industrial or large-scale applications—please contact us for availability.

What documentation comes with a selenium dioxide order?

Each order includes a Certificate of Analysis (CoA), Safety Data Sheet (SDS), and a Material Safety & Handling Guide for compliance and safety.

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