Which molecule has a bond order of 2 and is paramagnetic?
For O₂ : (sigma 1s)² (sigma^* 1s)² (sigma 2s)² (sigma^* 2s)² (sigma 2pz)² (pi 2px)² (pi 2py)² (pi^* 2px)¹ (pi^* 2py)¹ . Bonding = 10, antibonding = 6. Bond order = (10 - 6/2) = 2 , with 2 unpaired electrons (paramagnetic).
Ref: NCERT Class 11 Chemistry > Chapter 4: Chemical Bonding and Molecular Structure > Topic: Molecular Orbital Theory - MOT and Bond Order and Magnetic Properties