Beryllium nitride

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Beryllium nitride
Tl2O3structure.jpg
Identifiers
CAS number 1304-54-7 YesY
Properties
Molecular formula Be3N2
Molar mass 55.06 g/mol
Appearance yellow or white powder
Density 2.71 g/cm3
Melting point 2200 °C
Boiling point 2240 °C (decomp)
Solubility in water hydrolyzes
Structure
Crystal structure Cubic, cI80, SpaceGroup = Ia-3, No. 106 (α form)
Except where noted otherwise, 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),[1] unlike Beryllium azide or BeN6, it decomposes in vacuum into beryllium and nitrogen.[1] It is readily hydrolysed forming beryllium hydroxide and ammonia.[1] It has two polymorphic forms cubic α-Be3N2 with a defect anti-fluorite structure, and hexagonal β-Be3N2.[1] It reacts with silicon nitride, Si3N4 in a stream of ammonia at 1800–1900°C to form BeSiN2.[1]

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[2] 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 d e Egon Wiberg, Arnold Frederick Holleman (2001) Inorganic Chemistry, Elsevier ISBN 0-12-352651-5
  2. ^ Hugh O. Pierson, 1996, Handbook of Refractory Carbides and Nitrides: Properties, Characteristics, Processing, and Applications, William Andrew Inc.,ISBN 0-8155-1392-5