The species with fractional bond order is :

There are some species given below. (i) O_(2)^(+) (ii) CO (iii) B_(2) (iv) O_(2)^(-) (v) NO^(+) (vi) He_(2)^(+) (vii) C_(2)^(2+) (vii) CN^(-) (ix) N_(2)^(-) total number of species which have fractional bond order.

Consider the following species and find the total number of species which have fractional bond order : O_(2)^(+) , CO,B_(2) , O_(2)^(-) , NO^(+) , He_(2)^(+) , C_(2)^(2+) , CN^(-) , N_(2)^(-)

The pair of species with the same bond order is :

The pair of species with the same bond order is :