Stannous Oxide

Description

Stannous Oxide · CAS 21651-19-4 · OSn. Melting Point: 1976 °F@600 mmHg (decomposes); Melting Point: 1630 °C; Melting Point: (600 mmHg): 1976 °F (Decomposes).

Identification

CAS Registry Number	21651-19-4
PubChem CID	88989
Molecular formula	OSn
IUPAC name	oxotin

Computed Descriptors

Molecular Weight	134.71
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	1
Rotatable Bond Count	0
Exact Mass	135.897117
Monoisotopic Mass	135.897117
Topological Polar Surface Area	17.1
Heavy Atom Count	2
Formal Charge	0
Complexity	2

Physical & Chemical Properties

Melting Point	1976 °F@600 mmHg (decomposes)
Melting Point	1630 °C
Melting Point	(600 mmHg): 1976 °F (Decomposes)
Density	6.45 g/cm³
Density	6.3
Density	6.95 @25 °C
Vapor Pressure	0 mmHg (approx) (NIOSH, 2024)
Vapor Pressure	0 mmHg
Vapor Pressure	0 mmHg (approx)

Physical description & handling notes

• Tin(ii) oxide appears as brownish-black powder or black to blue-black crystalline solid. Mp: 1080 °C (decomposes); density: 6.45 g cm-3. Insoluble in water.
• Dry Powder
• Brownish-black solid; [Merck Index] Bluish-black odorless powder; [Alfa Aesar MSDS]
• BLUE-TO-BLACK CRYSTALLINE POWDER.
• Brownish-black powder or black to blue-black crystalline solid.
• Brownish-black powder.

Regulatory Status

GHS notification summary	64.7% (130 / 201)

GHS Hazard Classification

GHS notification summary	64.7% (130 / 201)
Reported hazard statements	H302 (35.3%), H317 (35.3%), H319 (35.3%), H372 (35.3%)

Documented Uses

• Tin oxides are used in solders, protective coatings, and alloys; [ACGIH] Used as a reducing agent and to make stannous salts; [Merck Index] Used to make gold-tin and copper-tin ruby glass; [INCHEM CICADS]
• Abrasive Blasting [Category: Clean]
• Metal Preparation and Pouring [Category: Foundry]
• Soldering [Category: Heat or Machine]
• Semiconductor Manufacturing [Category: Industry]
• Textiles (Printing, Dyeing, or Finishing) [Category: Industry]

Synonyms

Tin(II) oxide; 21651-19-4; Tin monoxide; Tin oxide (Sn2O2); Tin (II) Oxide; stannanone; TIN PROTOXIDE; RefChem:1100132; 244-499-5; TIN OXIDE (SnO); Tin(2+) oxide; oxotin; MFCD00011243; T 1186; Tego RL; Tin dioxide; Tin dioxide (SnO2); Tin(IV) oxide; (oxo)stannane; Tin Oxide Nanowires

Frequently Asked Questions

What are the CAS number and molecular formula of Stannous Oxide?

CAS 21651-19-4; molecular formula OSn; molecular weight — g/mol.

What other names is Stannous Oxide known by?

Tin(II) oxide, 21651-19-4, Tin monoxide, Tin oxide (Sn2O2), Tin (II) Oxide, stannanone.

Is Stannous Oxide classified as hazardous?

64.7% of GHS notifications report no hazard classification (130 of 201).

What are the key physical properties of Stannous Oxide?

Melting Point: 1976 °F@600 mmHg (decomposes); Melting Point: 1630 °C; Melting Point: (600 mmHg): 1976 °F (Decomposes); Density: 6.45 g/cm³.

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.