Saturday, December 01, 2012

La Quimica del Boro

Boron naturally occurs in borax . It is isolated by reduction with magnesium

Boron hydrides are the best fuels known. They are pyrophoric, however, and ignite upon contact with the atmosphere. In addition to being toxic, boron hydrides also yield high-mass B(OH)3 (s) as exhaust which does not provide good thrust. The molecule B12 is icosahedral. Boric acid decomposes as

Boron Hydride (BH3) exists only as a reaction intermediate

It is a Lewis acid which forms BH, BH4CO, BH4NH3.
Diborane (B2H6) is a bridge-bonded compound:
It decomposes at 200  as

which are all 11-electron compounds. Additional reactions are

(-2229 kJ mol-1) and

(-1557 kJ mol-1).
The compound B5H9 has C symmetry. The number of bonding electrons are

which are allocated to bonds as
The compound B4H10 is icosahedral (with 12 vertices and 20 faces), and undergoes  hybridization. B3N3H6 is cycloborane with N's and B's occupying alternate sites in the ring.

No comments: