Beryllium carbide
Encyclopedia
Beryllium carbide, or Be2C, is a metal
carbide
. Similar to diamond
, it is a very hard compound.
and carbon
at elevated temperatures (above 900°C). It also may be prepared by reduction of beryllium oxide
with carbon at a temperature above 1,500°C:
Beryllium carbide decomposes very slowly in water:
The rate of decomposition is faster in mineral acids with evolution of methane
.
However, in hot concentrated alkali the reaction is very rapid, forming alkali metal beryllates and methane:
Metal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...
carbide
Carbide
In chemistry, a carbide is a compound composed of carbon and a less electronegative element. Carbides can be generally classified by chemical bonding type as follows: salt-like, covalent compounds, interstitial compounds, and "intermediate" transition metal carbides...
. Similar to diamond
Diamond
In mineralogy, diamond is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the conversion rate from diamond to graphite is negligible at ambient conditions...
, it is a very hard compound.
Preparation
Beryllium carbide is prepared by heating the elements berylliumBeryllium
Beryllium is the chemical element with the symbol Be and atomic number 4. It is a divalent element which occurs naturally only in combination with other elements in minerals. Notable gemstones which contain beryllium include beryl and chrysoberyl...
and carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...
at elevated temperatures (above 900°C). It also may be prepared by reduction of beryllium oxide
Beryllium oxide
Beryllium oxide , also known as beryllia, is an inorganic compound with the formula BeO. This colourless solid is a notable electrical insulator with a higher thermal conductivity than any other non-metal except diamond, and actually exceeds that of some metals. As an amorphous solid, beryllium...
with carbon at a temperature above 1,500°C:
- 2BeO + 3C → Be2C + 2CO
Beryllium carbide decomposes very slowly in water:
- Be2C + 2H2O → 2BeO + CH4
The rate of decomposition is faster in mineral acids with evolution of methane
Methane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...
.
- Be2C + 4 H+ → 2 Be2+ + CH4
However, in hot concentrated alkali the reaction is very rapid, forming alkali metal beryllates and methane:
- Be2C + 4OH- → 2 BeO22- + CH4