# Write the electron configuration of Co3+ (Cobalt 3+ ion) and please explain why.

## Question:

Write the electron configuration of Co{eq}^{3+} {/eq} (Cobalt 3+ ion) and please explain why.

## Electronic Configuration of an Ion :

Ion can be of two types : cation and an anion .

The electronic configuration of an ion depends upon the number of electrons gained or lost .

## Answer and Explanation:

The atomic number of Cobalt is 27 . Its electronic configuration is :

{eq}1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{7}4s^{2} {/eq}

The given ion is {eq}Co^{3+} {/eq} and it has lost three electrons . After loosing three electrons, the electronic configuration becomes :

{eq}1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{6}4s^{0} {/eq}