Boron trioxide

From Wikipedia, the free encyclopedia

Boron trioxide
General
Other names	Diboron trioxide, Boric acid, Boric oxide.
Molecular formula	B2O3.
Molar mass	69.6182 g/mol
Appearance	Colorless, glassy solid.
CAS number	[[1303-86-2]]
EINECS number	2151258
Properties
Density and phase	2.460 g.cm-3, liquid
Solubility in water	2.2 g/100 g H2O
Solubility in alcohol	Soluble
Solubility in ether	N/A
Melting point	450°C
Boiling point	1860°C
Acidity (pKa)	N/A
Structure
Molecular shape	N/A
Dipole moment	N/A
Hazards
MSDS	External MSDS
EU classification	N/A
R-phrases	N/A
S-phrases	N/A
PEL (US, OSHA)	N/A
IDLH (US, NIOSH)	N/A
Flash point	N/A
Autoignition temperature	N/A
Explosive limits in air	N/A
RTECS number	N/A
Supplementary data page
Structure & properties	n, εr, etc.
Thermodynamic data	Phase behaviour Solid, liquid, gas
Spectral data	UV, IR, NMR, MS
Related compounds
Other anions	None
Other cations	None
Related compounds	None
Except where noted otherwise, data are given for materials in their standard state (at 25°C, 100 kPa) Infobox disclaimer and references

Boron oxide is an odourless, colourless or white solid, also known as diboron trioxide, formula B₂O₃.

Contents 1 Applications 2 Hazard Information 3 Data 4 External links

[edit] Applications

• Fluxing agent for glass and enamels
• Starting material for synthesizing other Boron compounds such as Boron carbide
• An additive used in glass fibres (optical fibres)
• It is used in the production of borosilicate glass

[edit] Hazard Information

• Australian Government information
• [1] US NIH hazard information

[edit] Data

The standard enthalpy of formation of boron trioxide at 25^oC:

• in crystalline phase -302 kilo-cal/grm.mole
• in glassy phase -297.6 kilo-cal/grm.mole

The standard free energy of formation of boron trioxide at 25^oC:

• in crystalline phase -283 kilo-cal/grm.mole
• in glassy phase -280 kilo-cal/grm.mole

[edit] External links

• National Pollutant Inventory - Boron and compounds

• Links to external chemical sources