The correct option is D H−2
O2+2=σ1s2 σ∗ 1s2 σ2s2 σ∗2s2 σ2p2z (π2p2x=π2p2y)
(16-2=14)
Bond order =10−42=62=3
The bond order of O2−2 is
O2−2=σ1s2 σ∗1s2 σ2s2 σ∗ 2s2 σ2p2z(π2p2x=π2p2y)(π∗2p2x=π∗2p2y)
(18e−)
=10−82=22=1
The bond order of F2−2 is
F2(18)=σ1s2 σ∗ 1s2 σ2s2 σ∗2s2 σ2p2z (π2p2x=π2p2y) (π∗2p2x=π∗2p2y)
Bond order =10−82=22=1
Bond order for H−2 is:
(3)H−2σ1s2 σ∗ 1s1
Bond Order=2−12=12=0.5
Hence, option (d) is correct.