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

Options

A. 8.29,9.32
B. 9.32,9.32
C. 8.29,8.29
D. 9.32,8.29

Answer

D

Explanation

First ionisation potential of beryllium (Be) is greater than boron (B) due to stable configuration
`"'_(4)Be = 1s^(2),2s^(2)`
`""_(5)B = 1s^(2),2s^(2),2p^(1)`
Order of attraction of electrons towards nucleus is `2s gt 2p`, so more amount of energy is required to remove the electron from 2 s orbital in comparison to 2p orbital. So, ionisation potential of Be is 9.32 eV and Bis 8.29 eV