Among the following the paramagnetic compound is

Step-by-step solution

N a 2 O 2 or O 2 2 - = σ 1 s 2 σ * 1 s 2 , σ 2 s 2 σ * 2 s 2 , σ 2 p Z 2 , π 2 p X 2 = π 2 p Y 2 , π * 2 p X 2 = π * 2 p Y 2 Number of unpaired electrons = 0 N = N → O number of unpaired electrons = 0 O = O ⊕ – O - ↔ O = O → O Number of unpaired electrons = 0 K O 2 or O 2 - = σ 1 s 2 , σ * 1 s 2 σ 2 s 2 , σ * 2 s 2 , σ 2 p Z 2 , π 2 p X 2 = π 2 p Y 2 , π * 2 p X 2 = π * 2 p Y 1 Number of unpaired electrons = 1 So O 2 - is paramagnetic.