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C He+2<O−2<NO<C2−2Four diatomic species are listed below. Identify the correct order in which the bond order is increasing them,
First we will calculate the bond order for all elements.
Bond order=Nb−Na2
Nb=Number of electrons in bonding molecular orbital
Na=Number of electrons in anti0bonding molecular orbital
NO=15 electrons
σ1s2,σ∗1s2,σ2s2,σ∗2s2,σ2p2z,π2p2x=π2p2y,π∗2p1x
B.O=8−32=2.5
O−2=17 electrons
σ1s2,σ∗1s2,σ2s2,σ∗2s2,σ2p2z,π2p2x=π2p2y,,π∗2p2x=π∗2p1y
B.O=8−52=1.5
C2−2=14 electrons
σ1s2,σ∗1s2,σ2s2,σ∗2s2,σ2p2z,π2p2x=π2p2y
B.O=8−22=3
He2+2=3 electrons
σ1s2,σ∗1s1
B.O=2−12=0.5
Therefore order is He+2<O−2<NO<C2−2