Question

What is the no. of valence electrons in


sodium ion(Na+)

Oxide ion(O2-)


Given atomic no. of


Na=11

O=8

Answer 1

The electronic configuration of Na+ is 2, 8, 1 Na

 Na+ + 1e-

Now the electron configuration of Na+ is 2, 8.

Hence, the valence electrons are 8.

The electronic configuration of O2- is 2, 6. O

 O2- - 2e-

Now the electron configuration of O2- is 2, 8.

Hence, the valence electrons are 8.