Chromium's electron configuration is <span>1s2 2s2 2p6 3s2 3p6 3d5 4s1, where the last electron is in the s orbital with only 1. As for Li, it is found in the group 1 metals, and it is a fact that all elements under this group has the their last electron to be in the s orbital with only one electron in their outermost shell.
</span>The electron configuration<span> associated with the lowest energy level of the atom is referred to as </span>ground state and each electron ion is in the lowest energy level possible. When the moment comes that electrons go into a higher level of energy, that is what we call the excited state.
