Practice question
Question
Which of the following d-block elements in period 4 has an exceptional electronic configuration?
Explanation
Cr (Z=24) has an exceptional configuration (3d⁵ 4s¹) due to the stability of a half-filled 3d subshell, unlike Sc (3d¹ 4s²), Mn (3d⁵ 4s²), or Fe (3d⁶ 4s²).