Names | |
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IUPAC name
Boron nitride
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Identifiers | |
3D model (JSmol)
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ChEBI | |
ChemSpider | |
ECHA InfoCard | 100.030.111 |
EC Number | 233-136-6 |
216 | |
MeSH | Elbor |
PubChem CID
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RTECS number | ED7800000 |
UNII | |
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Properties | |
BN | |
Molar mass | 24.82 g·mol−1 |
Appearance | Colorless crystals |
Density | 2.1 (h-BN); 3.45 (c-BN) g/cm3 |
Melting point | 2,973 °C (5,383 °F; 3,246 K) sublimates (cBN) |
insoluble | |
Electron mobility | 200 cm2/(V·s) (cBN) |
Refractive index (nD)
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1.8 (h-BN); 2.1 (c-BN) |
Structure | |
hexagonal, sphalerite, wurtzite | |
Thermochemistry | |
19.7 J/(K·mol) | |
Std molar
entropy (S |
14.8 J/K mol |
Std enthalpy of
formation (ΔfH |
-254.4 kJ/mol |
Gibbs free energy (ΔfG˚)
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-228.4 kJ/mol |
Hazards | |
EU classification (DSD) (outdated)
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Xi |
R-phrases (outdated) | R36/37 |
S-phrases (outdated) | S26, S36 |
NFPA 704 | |
Related compounds | |
Related compounds
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Boron arsenide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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what is ?) | (|
Infobox references | |
Boron carbide
Boron phosphide
Boron trioxide
Boron nitride is a heat- and chemically resistant refractory compound of boron and nitrogen with the chemical formula BN. It exists in various crystalline forms that are isoelectronic to a similarly structured carbon lattice. The hexagonal form corresponding to graphite is the most stable and soft among BN polymorphs, and is therefore used as a lubricant and an additive to cosmetic products. The cubic (sphalerite structure) variety analogous to diamond is called c-BN; it is softer than diamond, but its thermal and chemical stability is superior. The rare wurtzite BN modification is similar to lonsdaleite and may even be harder than the cubic form.
Because of excellent thermal and chemical stability, boron nitride ceramics are traditionally used as parts of high-temperature equipment. Boron nitride has potential use in nanotechnology. Nanotubes of BN can be produced that have a structure similar to that of carbon nanotubes, i.e. graphene (or BN) sheets rolled on themselves, but the properties are very different.
Boron nitride exists in multiple forms that differ in the arrangement of the boron and nitrogen atoms, giving rise to varying bulk properties of the material.
The amorphous form of boron nitride (a-BN) is non-crystalline, lacking any long-distance regularity in the arrangement of its atoms. It is analogous to amorphous carbon.