The paramagnetic behaviour of `B_2` is due to the presence of

Options

A. 2 unpaired electrons in `pi_(n) MO`
B. `2 unpaired electrons in `pi^(**) MO`
C. 2 unpaired electrons in `sigma^(**)MO`
D. 2 unpaired electrons in `sigma_(b)MO`

Answer

A

Explanation

`B_(2)`(electrons=10)
`sigma(1s)^(2),sigma^(**)(1s)^(2),sigma(2s)^(2),sigma^(**)(2s)^(2),pi(2p_(x))^(1),pi(2p_(y))^(1)`
Thus paramagnetic behaviour of `B_(2)` is due to the presence of two unpaired electrons in `pi`-bonding molecular orbital.