CGPET 2017 Solved Paper

Bond order (BO) Number of Bonding electrons =

−Number of non - bonding electrons

2

Total number of electrons in CN⊖ ions
=6+7+1=14
MO configuration of CN⊖ ion
=σ1s2,σ*1s2,σ2s2,σ*2s2,π2px2 ≈π2py2,σ2pz2
and number of bonding electrons =10
Number of non-bonding Electrons =4
∴B.O=

10−4

2

=3