What is the electron configuration of iron iii?

1 Answer
Jun 3, 2018

#1s^2\2s^2\2p^6\3s^2\3p^6\3d^5#

Explanation:

Iron(III) is the ion of iron in its #3+# oxidation state, meaning that it has lost #3# electrons from its valence shell.

The standard electron configuration for an iron atom is:

#1s^2\2s^2\2p^6\3s^2\3p^6\3d^6\4s^2#

Check to see if the total electrons add up to the proton number of the iron, which is #26#.

Now, for iron to lose three electrons, it'll lose its outermost #4s# electrons (both of them), and one of its #3d# electrons. This leaves a configuration of:

#1s^2\2s^2\2p^6\3s^2\3p^6\3d^5#