Question

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

(a) 8.29,8.29

(b) 9.32,9.32

(c) 8.29,9.32

(d) 9.32,8.29

Answer 1

The correct option is: (d) 9.32,8.29

Explanation:

4Be → 1s2 2s2, 5B → 1s2 2s2 2p1

Due to stable fully-filled '*'-orbital arrangement of electrons in 'Be' atom, more energy is required to remove an electron from the valence shell than 'B' atom. Therefore 'Be' has higher ionization potential than 'B'.