Beryllium nitride

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Beryllium nitride
Tl2O3structure.jpg
Identifiers
1304-54-7 YesY
ECHA InfoCard 100.013.757
Properties
Be3N2
Molar mass 55.06 g/mol
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 in [[acids, bases]] hydrolyzes
Structure
Cubic, cI80, SpaceGroup = Ia-3, No. 106 (α form)
Hazards
US health exposure limits (NIOSH):
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]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

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[edit]

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

Uses[edit]

It is used in refractory ceramics[3] as well as in nuclear reactors and to produce radioactive carbon-14 for tracer applications.

Reactions[edit]

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[edit]

  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