Selenium oxide

Description

Selenium oxide · CAS 7446-08-4 · O2Se. UNII 9N3UK29E57. Melting Point: 340 °C under pressure; Solubility: In water, 400 g/L at 20 °C; Solubility: 264 g/100 g water at 22 °C.

Identification

CAS Registry Number	7446-08-4
PubChem CID	24007
Molecular formula	O2Se
IUPAC name	selenium dioxide
UNII (FDA)	9N3UK29E57

Computed Descriptors

Molecular Weight	110.97
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	2
Rotatable Bond Count	0
Exact Mass	111.90635
Monoisotopic Mass	111.90635
Topological Polar Surface Area	34.1
Heavy Atom Count	3
Formal Charge	0
Complexity	18.3

Physical & Chemical Properties

Melting Point	340 °C under pressure
Solubility	In water, 400 g/L at 20 °C
Solubility	264 g/100 g water at 22 °C
Density	3.954 at 15 °C/15 °C
Density	Density (at 15 °C): 3.95 g/cm³
Density	3.95 @25 °C
Odor Threshold	0.0002 mg/cu m
Odor Threshold	Air: 2.0 ppm

Physical description & handling notes

• Selenium dioxide appears as a white or creamy-white volatile lustrous crystal or crystalline powder with a pungent sour smell. Melting point 340 deg C. Density 3.954 g / cm3. Toxic by ingestion and inhalation.
• White or yellowish-white to slightly reddish, lustrous, crystalline powder or needles. [HSDB]
• LUSTROUS WHITE HYGROSCOPIC CRYSTALS OR POWDER. ITS YELLOWISH GREEN VAPOUR HAS A PUNGENT SOUR SMELL.
• Lustrous tetragonal needles; yellowish green vapor
• Vapor has a pungent sour smell
• Rotten radishes.

GHS Hazard Classification

Reported hazard statements	H301 (100%), H314 (10.2%), H318 (10.2%), H331 (89.8%), H373 (100%), H400 (52.3%), H410 (100%), H319

Documented Uses

• Used to make other selenium compounds; Also used as a reagent and oxidizing agent; [Merck Index #8434]
• Photographic Processing [Category: Other]
• Glass Manufacturing [Category: Industry]
• Glassblowing [Category: Hobbies]
• In the manufacture of other selenium compounds.
• Analysis (testing for alkaloids), oxidizing agent, antioxidant in lubricating oils, catalyst.

Synonyms

SELENIUM DIOXIDE; 7446-08-4; Selenious anhydride; Selenium oxide (SeO2); Selenium dioxide dimer; Selenous acid anhydride; Selenium oxide (Se2O4); Selenium(IV) dioxide (1:2); Selenium oxide (1:2); 9N3UK29E57; DTXSID4021264; NSC-56753; Oxide, Selenium; (oxo-lambda4-selanylidene)oxidane; RefChem:389275; 231-194-7

Frequently Asked Questions

What are the CAS number and molecular formula of Selenium oxide?

CAS 7446-08-4; molecular formula O2Se; molecular weight — g/mol.

What other names is Selenium oxide known by?

SELENIUM DIOXIDE, 7446-08-4, Selenious anhydride, Selenium oxide (SeO2), Selenium dioxide dimer, Selenous acid anhydride.

Is Selenium oxide classified as hazardous?

Hazard statements reported: H301, H314, H318, H331, H373.

What are the key physical properties of Selenium oxide?

Melting Point: 340 °C under pressure; Solubility: In water, 400 g/L at 20 °C; Solubility: 264 g/100 g water at 22 °C; Density: 3.954 at 15 °C/15 °C.

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.