What are the electronic configurations of common atomic ions?

1 Answer
Nov 8, 2016

Usually the electronic configuration is the same as that of the NEAREST inert gas.

Explanation:

Excluding the transition metals, the common ions of the 1st short rows are the same as that of the neutral inert gas. Consider the common ions of nitrogen, N^(3-), O^(2-), and F^(-); all of these ions have 8 valence electrons, and a formal electronic configuration of 1s^(2)2s^(2)2p^6. While these ions have negative charges, these are isolelectronic with [Ne], the inert gas with 8 valence electrons.

Na^+, and Mg^(2+) in the same way have the same formal [Ne] configuration. Why?

How do you propose to represent P^(3-), S^(2-), and Cl^-?