Which of the following species is paramagnetic with two unpaired electrons in pi anti bonding molecular orbital
O2
O2+
O2-
O2-2
O2-2-KK'σ2s2σ2s*2σ2pz2π2px2π2py2π2px*2π2py*2
O2--KK'σ2s2σ 2s*2σ2pz2π2py2π2py2π2px*2π2py*1
O2 -KK'σ2s2σ2s*2σ2pz2π2px2π2py2π2px*1π2py*1
O2+-KK'σ2s2σ2s*2σ2pz2π2px2π2py2π2px*1π2py*0
Bond order in
O2-2=10-82=1; O2-=10-72=1.5; O2=10-62=2; O2+=10-52=2.5;
O — O bond length in
O2-2>O2->O2>O2+