According to molecular orbital theory, which of the following is true with respect to `LI_(2)+"and"Li_(2)-?`

Options

A. Both are unstable
B. `Li^(2+)` is unstable and `Li_(2)^(-)` is stable
C. `Li_(2)^(+)` is stable and `Li_(2)^(-)` is unstable
D. Both are stable

Answer

D

Explanation

`Li_(2):(sigma1s)^(2)(sigma^(**)1s)^(2)(sigma2s)^(2)`
`Li_(2)^(+):(sigma1s)^(2)(sigma2s)^(1)`
`"Bond order "=(3-2)/(2)=(1)/(2)`
`Li_(2)^(-):(sigma1s)^(2)(sigma^(**)1s)^(2)(sigma2s)^(2)(sigma^(**)2s)^(1)`
`"Bond order"=(4-3)/(2)=(1)/(2)`
Both have bond order of 0.5 and are stable.