Question

From which of the following species, it is easiest to remove one electron?

• A. $O\left(\text{g}\right)$
• B. $O^{2-}\left(\text{g}\right)$
• C. $O^{+}\left(\text{g}\right)$
• D. $O^{-}\left(\text{g}\right)$

Answer 1

The correct option is B

$O^{2-}\left(\text{g}\right)$

$O^{2-}$ has two electrons more than the number of protons which means that there will be greater inter-electronic repulsions among the valence electrons. For such a small ion, there is no scope for the excess electronic charge to be dispersed through the volume and hence it is easier to remove one electron from an $O^{2-}$ anion.