Boron nitride
| 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 |
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| 216 | |
| MeSH | Elbor |
PubChem CID
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| RTECS number |
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| UNII | |
CompTox Dashboard (EPA)
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| Properties | |
| BN | |
| Molar mass | 24.82 g/mol |
| Appearance | Colorless crystals |
| Density | 2.1 g/cm3 (h-BN); 3.45 g/cm3 (c-BN) |
| Melting point | 2,973 °C (5,383 °F; 3,246 K) sublimates (c-BN) |
| Insoluble | |
| Electron mobility | 200 cm2/(V·s) (c-BN) |
Refractive index (nD)
|
1.8 (h-BN); 2.1 (c-BN) |
| Structure | |
| Hexagonal, sphalerite, wurtzite | |
| Thermochemistry | |
Heat capacity (C)
|
19.7 J/(K·mol) |
Std molar
entropy (S⦵298) |
14.8 J/K mol |
Std enthalpy of
formation (ΔfH⦵298) |
−254.4 kJ/mol |
Gibbs free energy (ΔfG⦵)
|
−228.4 kJ/mol |
| Hazards | |
| GHS labelling: | |
| Warning | |
| H319, H335, H413 | |
| P261, P264, P271, P273, P280, P304+P340, P305+P351+P338, P312, P337+P313, P403+P233, P405, P501 | |
| NFPA 704 (fire diamond) | |
| Related compounds | |
Related compounds
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references
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Boron nitride is a thermally 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 (zincblende aka sphalerite structure) variety analogous to diamond is called c-BN; it is softer than diamond, but its thermal and chemical stability is superior.
Because of excellent thermal and chemical stability, boron nitride ceramics are used in high-temperature equipment and metal casting. Boron nitride has potential use in nanotechnology.