Chemistry

Problem

The neutral atom of element X has the ground-state electron configuration

[\text{Ar}]\,4s^{1}\,3d^{5}

. An ion of X has the configuration

[\text{Ar}]\,3d^{5}

. Which of the following is the correct symbol for this ion? a)

\text{Fe}^{3+}

\text{Cr}^{2+}

\text{Cr}^{+}

\text{Mn}^{2+}