Iron plays a central role in biological redox chemistry by cycling between multiple oxidation states. Consider the electronic structure of iron and one of its common ions.
(a) Write the complete ground-state electron configuration for a neutral iron atom.
(b) Determine the ground-state electron configuration of the Fe3+ ion. Clearly indicate any electrons removed and the order in which they are removed.
(c) Draw an orbital-box diagram showing the distribution of electrons in the 3d subshell of Fe3+.
(d) Compare the number of unpaired electrons in Fe2+ and Fe3+. Explain how this difference accounts for the observed greater magnetic susceptibility of aqueous Fe3+ salts relative to aqueous Fe2+ salts.