Question

The least stable ion among the following is
A. `Li^(o+)`
B. `B^(ɵ)`
C. `C^(ɵ)`
D. `Be^(ɵ)`

Answer 1

Correct Answer - D
`Li = 1s^(2) 2s^(1), Be = 1s^(2), 2s^(2), B = 1s^(@), 2s^(2), 2p^(1)`, `C = 1s^(2), 2s^(2)2p^(2)`.
`Be` is highly stable due to filled s-orbitals, therefore `Be^(ɵ)` is highly unstable.