Beryllium carbide

Beryllium carbide, or Be₂C, is a metal carbide. Similar to diamond, it is a very hard compound. It is used in nuclear reactors as a core material.

Beryllium carbide

Names
IUPAC name Beryllium carbide
Identifiers
CAS Number	506-66-1 Y
3D model (JSmol)	Interactive image
ChemSpider	61480 Y
ECHA InfoCard	100.007.319
EC Number	208-050-7
PubChem CID	68173
UNII	F5D2F26ONX Y
CompTox Dashboard (EPA)	DTXSID6060137
InChI InChI=1S/C.2Be Y Key: UQVOJETYKFAIRZ-UHFFFAOYSA-N Y
SMILES [Be]=C=[Be]
Properties
Chemical formula	CBe2
Molar mass	30.035 g·mol−1
Appearance	Yellow to red crystals
Odor	odorless
Density	1.90 g cm−3 (at 15 °C)
Melting point	2,100 °C (3,810 °F; 2,370 K) (decomposes)
Solubility in water	decomposes
Structure
Crystal structure	cubic
Related compounds
Related compounds	Carbon dioxide Carbon diselenide Carbon disulfide
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)
REL (Recommended)	Ca C 0.0005 mg/m3 (as Be)
IDLH (Immediate danger)	Ca [4 mg/m3 (as Be)]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Preparation

Beryllium carbide is prepared by heating the elements beryllium and carbon at elevated temperatures (above 950°C). It also may be prepared by reduction of beryllium oxide with carbon at a temperature above 1,500°C:

2BeO + 3C → Be₂C + 2CO

Beryllium carbide decomposes very slowly in water and forms methane gas:

Be₂C + 2H₂O → 2BeO + CH₄

The rate of decomposition is faster in mineral acids with evolution of methane.

Be₂C + 4 H⁺ → 2 Be²⁺ + CH₄

In hot concentrated alkali the reaction is very rapid, forming alkali metal beryllates and methane:

Be₂C + 4OH⁻ → 2 BeO₂²⁻ + CH₄

See also

• Carbide

External links

• MATERIAL SAFETY DATA SHEET
• Encyclopædia Britannica
• Electrochemical Society article
• ASC website
• article in Nature
• NIST government website