L.C.A.O. Principle is involved in the formationof the molecular orbitals according ot molecular orbital theory. The energy of the bonding molecular orbital is less than that of thecombining atomic orbitals while that of the antibonding molecular orbitals while that of the order `(B.O.)=1/2(N_(b)-N_(a))` helps in predicting (i) formation of molecules/molecular ions, bond dossociation energy, stability and bond length. Only the molecules or ions with positive B.O. can be formed. These will be diamagnetic if all molecular orbitals are dilled and paramagnetic if one of more are half filled. The atomic prbitals at the time of overlap must have the same symmetry as well.
The bond order (B.O.) in `B_(2)` molecule is:

Options

A. 0
B. 1
C. 2
D. 3

Answer

B

Explanation

B.O. is one
`B_(2)=[sigma_(1s)]^(2)[sigma_(1s)^(**)]^(2)[sigma_(2s)]^(2)[sigma_(2s)^(**)]^(2)[pi_(2px)]^(1)[pi_(2py)]^(1)`