Consider the following species: CN+,CN-, NO and CN. Which one of these will have the highest bond order [2018]
(2)
NO(15): (σ1s)2,(σ*1s)2,(σ2s)2,(σ*2s)2,(σ2pz)2,(π2px)2=(π2py)2,(π*2px)1=(π*2py)0 B.O.=10-52=2.5
CN-(14): (σ1s)2,(σ*1s)2,(σ2s)2,(σ*2s)2,(π2px)2=(π2py)2,(σ2pz)2 B.O.=10-42=3
CN(13): (σ1s)2,(σ*1s)2,(σ2s)2,(σ*2s)2,(π2px)2=(π2py)2,(σ2pz)1 B.O.=9-42=2.5
CN+(12): (σ1s)2,(σ*1s)2,(σ2s)2,(σ*2s)2,(π2px)2=(π2py)2 B.O.=8-42=2
Hence, CN- has highest bond order.