The first ionisation potentials (eV) of `Be` and `B` respectively are

Options

A. `8.29, 9. 32`
B. `9.32, 8.29 `
C. `9. 32, 9.32`
D. `8. 29 ,8 . 29`

Answer

B

Explanation

Be has higher `Delta_(i) H_(1)` than B because in Be ` (1s^(2) 2s^(2))` the last elctronic is to be removed from a fully filled 2s-orbital while in B `(1s^(2) 2s^(2) 2p^(1))` the last electron is to be remvoed from a less tightly held 2p- electron.