Jump to content

Beryllium nitride

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Anastrophe (talk | contribs) at 18:53, 9 June 2024 (Rollback edit(s) by ASChem22 (talk): Reverting good faith edits: SPA linkspamming (UV 0.1.5)). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Beryllium nitride
Names
IUPAC name
Beryllium nitride
Other names
triberyllium dinitride
Identifiers
3D model (JSmol)
ECHA InfoCard 100.013.757 Edit this at Wikidata
EC Number
  • 215-132-6
UNII
  • InChI=1S/3Be.2N
  • InChI=1S/3Be.2N/q3*+2;2*-3
  • InChI=1S/3Be.2N/q;;+2;2*-1
  • [Be]=N[Be]N=[Be]
  • [Be+2].[Be+2].[Be+2].[N-3].[N-3]
  • [Be]=[N-].[Be+2].[N-]=[Be]
Properties
Be3N2
Molar mass 55.051 g·mol−1
Appearance yellow or white powder
Density 2.71 g/cm3
Melting point 2,200 °C (3,990 °F; 2,470 K)
Boiling point 2,240 °C (4,060 °F; 2,510 K) (decomposes)
decomposes
Solubility decomposes in solutions of acid and base
Structure
Cubic, cI80, SpaceGroup = Ia-3, No. 206 (α form)
Hazards
NIOSH (US health exposure limits):
PEL (Permissible)
TWA 0.002 mg/m3
C 0.005 mg/m3 (30 minutes), with a maximum peak of 0.025 mg/m3 (as Be)[1]
REL (Recommended)
Ca C 0.0005 mg/m3 (as Be)[1]
IDLH (Immediate danger)
Ca [4 mg/m3 (as Be)][1]
Related compounds
Other cations
Calcium nitride
Magnesium nitride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Beryllium nitride, Be3N2, is a nitride of beryllium. It can be prepared from the elements at high temperature (1100–1500 °C);[2] unlike beryllium azide or BeN6, it decomposes in vacuum into beryllium and nitrogen.[2] It is readily hydrolysed forming beryllium hydroxide and ammonia.[2] It has two polymorphic forms cubic α-Be3N2 with a defect anti-fluorite structure, and hexagonal β-Be3N2.[2] It reacts with silicon nitride, Si3N4 in a stream of ammonia at 1800–1900 °C to form BeSiN2.[2]

Preparation

Beryllium nitride is prepared by heating beryllium metal powder with dry nitrogen in an oxygen-free atmosphere in temperatures between 700 and 1400 °C.

3Be + N2 → Be3N2

Uses

It is used in refractory ceramics[3] as well as in nuclear reactors.

It is used to produce radioactive carbon-14 for tracer applications by the 14
7
N
+ n → 14
6
C
+ p reaction. It is favoured due to its stability, high nitrogen content (50%), and the very low cross section of beryllium for neutrons.[4]

Reactions

Beryllium nitride reacts with mineral acids producing ammonia and the corresponding salts of the acids:

Be3N2 + 6 HCl → 3 BeCl2 + 2 NH3

In strong alkali solutions, a beryllate forms, with evolution of ammonia:

Be3N2 + 6 NaOH → 3 Na2BeO2 + 2 NH3

Both the acid and alkali reactions are brisk and vigorous. Reaction with water, however, is very slow:

Be3N2 + 6 H2O → 3 Be(OH)2 + 2 NH3

Reactions with oxidizing agents are likely to be violent. It is oxidized when heated at 600 °C in air.

References

  1. ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0054". National Institute for Occupational Safety and Health (NIOSH).
  2. ^ a b c d e Egon Wiberg, Arnold Frederick Holleman (2001) Inorganic Chemistry, Elsevier ISBN 0-12-352651-5
  3. ^ Hugh O. Pierson, 1996, Handbook of Refractory Carbides and Nitrides: Properties, Characteristics, Processing, and Applications, William Andrew Inc.,ISBN 0-8155-1392-5
  4. ^ Shields, R. P. (1956-02-01). THE PRODUCTION OF C$sup 14$ BY THE Be$sub 3$N$sub 2$ PROCESS (Report). Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States).