Sodium Tetraborate

Description

Sodium Tetraborate · CAS 1330-43-4 · B4Na2O7. UNII 8191EN8ZMD. Boiling Point: 1,575 °C (decomposes); Melting Point: 743 °C; Melting Point: 742 °C.

Identification

CAS Registry Number	1330-43-4
PubChem CID	10219853
Molecular formula	B4Na2O7
IUPAC name	disodium;3,7-dioxido-2,4,6,8,9-pentaoxa-1,3,5,7-tetraborabicyclo[3.3.1]nonane
UNII (FDA)	8191EN8ZMD

Computed Descriptors

Molecular Weight	201.2
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	7
Rotatable Bond Count	0
Exact Mass	201.9811616
Monoisotopic Mass	201.9811616
Topological Polar Surface Area	92.3
Heavy Atom Count	13
Formal Charge	0
Complexity	121

Physical & Chemical Properties

Boiling Point	1,575 °C (decomposes)
Melting Point	743 °C
Melting Point	742 °C
Melting Point	1366 °F
Solubility	4%
Density	2.367
Density	2.37
Vapor Pressure	Negligible at 20 °C
Vapor Pressure	0 mmHg (approx)
pH	pH = 9.3 at 20 °C (3% solution)

Physical description & handling notes

• Liquid; Liquid; Other Solid; Dry Powder; Large Crystals; Large Crystals; Dry Powder; Other Solid
• Powder or glass-like plates becoming opaque on exposure to air; slowly soluble in water
• White to gray, odorless powder; Becomes opaque on exposure to air; [NIOSH]
• COLOURLESS-TO-WHITE HYGROSCOPIC CRYSTALS OR POWDER. TURNS OPAQUE ON EXPOSURE TO AIR.
• White to gray, odorless powder.
• White to gray, odorless powder. [herbicide] [Note: Becomes opaque on exposure to air.]

Regulatory Status

Regulatory & Food Contact	PRESERVATIVE: Food Additives BORAX NO ADI ALLOCATED NMRS 31/TRS 228-JECFA 6/37

GHS Hazard Classification

Reported hazard statements	H319 (53.2%), H360 (88.5%), H315, H335, H370, H372, H320, H373

Documented Uses

• Acid and Alkali Cleaning of Metals [Category: Clean]
• Using Disinfectants or Biocides [Category: Clean]
• Glass Manufacturing [Category: Industry]
• Manufacture of glass, enamels, & other ceramic products
• Soldering metals; manufacture of glazes and enamels; tanning; in cleaning compounds; artificially aging wood; ...curing and preserving skins
• As preservative either alone or with other antiseptics against wood fungus; fireproofing fabrics & wood

Synonyms

1330-43-4; Sodium Tetraborate, Anhydrous; Borax glass; Boron sodium oxide (B4Na2O7); Anhydrous borax; Sodium biborate; Borax Anhydrous; Fused borax; Sodium borate anhydrous; Borax, fused; Sodium pyroborate; Dehybor; Granubor; Spraybor; Sodium borate, anhydrous; Borax, dehydrated

Frequently Asked Questions

What are the CAS number and molecular formula of Sodium Tetraborate?

CAS 1330-43-4; molecular formula B4Na2O7; molecular weight — g/mol.

What other names is Sodium Tetraborate known by?

1330-43-4, Sodium Tetraborate, Anhydrous, Borax glass, Boron sodium oxide (B4Na2O7), Anhydrous borax, Sodium biborate.

What is the regulatory status of Sodium Tetraborate?

Documented regulatory listings: PRESERVATIVE: Food Additives; BORAX; NO ADI ALLOCATED.

Is Sodium Tetraborate classified as hazardous?

Hazard statements reported: H319, H360, H315, H335, H370.

What are the key physical properties of Sodium Tetraborate?

Boiling Point: 1,575 °C (decomposes); Melting Point: 743 °C; Melting Point: 742 °C; Melting Point: 1366 °F.

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.