Which of the following electronic configurations represents an EXCITED state of an atom? — Periodic Table and Periodicity Chemistry Question

💡 Solution & Explanation

An excited state occurs when electrons occupy higher energy levels before lower energy levels are fully filled. In A, the $2p$ subshell is incomplete ($2p^5$) while the higher $3s$ subshell has an electron (Excited Neon). In D, the $2p$ is incomplete ($2p^4$) while $3s$ is filled. B is the ground state of $Cr$ (anomalous half-filled stability). C is the ground state of $Sc$.