A m o n g   H 2 ,   H e 2 + ,   L i 2 ,   B e 2 ,   B 2   , C 2 ,   N 2 ,   O 2 - ,   a n d   F 2   , the number of diamagnetic species is - (Atomic number : H   =   1 ,   H e   =   2 ,   L i   =   3 ,   B e   =   4 ,   B   =   5 ,   C   =   6 ,   N   =   7 , &#160

Step-by-step solution

H 2 ⇒ σ 1 s 2 (Diamagnetic) H e 2 + ⇒ σ 1 s 2 σ * 1 s 1 (Paramagnetic) L i 2 ⇒ σ 1 s 2 σ * 1 s 2 σ 2 s 2 (Diamagnetic) B e 2 ⇒ σ 1 s 2 σ * 1 s 2 σ 2 s 2 σ * 2 s 2 (Does not exist) B 2 ⇒ σ 1 s 2 σ * 1 s 2 σ 2 s 2 σ * 2 s 2 π 2 p x 1 = π 2 p y 1 (Paramagnetic) C 2 ⇒ σ 1 s 2 σ * 1 s 2 σ 2 s 2 σ * 2 s 2 π 2 p x 2 = π 2 p y 2 (Diamagnetic) N 2 ⇒ σ 1 s 2 σ * 1 s 2 σ 2 s 2 σ * 2 s 2 π 2 p x 2 = π 2 p y 2 σ 2 p z 2 (Diamagnetic) O 2 Θ ⇒ 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