Which of the following has the highest bond order ?

Options

A. `N_(2)`
B. `O_(2)`
C. `He_(2)`
D. `H_(2)`

Answer

A

Explanation

Molecular orbital configuration of
`N_(2)rArr sigma 1s^(2)sigma^(**)1s^(2)sigma 2s^(2)sigma^(**)2s^(2)pi 2p_(x)^(2)pi 2p_(y)^(2)sigma 2p_(z)^(2)`.
Bond order `=(1)/(2)(10-4)=3`
`O_(2)rArr sigma 1s^(2)sigma^(**)1s^(2)sigma2s^(2)sigma^(**)2s^(2)sigma 2p_(z)^(2)pi 2p_(x)^(2)pi2p_(y)^(2) pi^(**)2p_(x)^(1)pi^(**)2p_(y)^(1)`
Bond order `=(1)/(2)(10-6)=2`
`He_(2)rArr sigma 1s^(2)sigma^(**)1s^(2)`, Bond order `=(1)/(2)(2-2)=0`
`H_(2)rArr sigma 1s^(2)` , Bond order `=(1)/(2)(2-0)=1`