Aufbau rule is not followed, 19th electron is Fe(Z-21) will have
Atoms have extra stability in three forms of electronic configuration: it has completely filled, half filled or empty orbitals. Fe=1S2, 2S2, 2P6, 3S2, 3P6, 4S2, 3d6, 4S2 So according to 3d it has n=3 and l=2.
645 MCQ for effective preparation of the test of Basics of Chemistry section.
Read the MCQ statement: Aufbau rule is not followed, 19th electron is Fe(Z-21) will have , keenly and apply the method you have learn through the video lessons for Basics to give the answer. Record your answer and check its correct answer and video explanation for MCQ No. 125-2311.