Question

Explain aufbau principle for scandium

Answer 1

Explanation:

Scandium has three valence electrons. The aufbau principle tells us they should add to the lowest available energy sublevel. Therefore, the first electron goes into 3d. ... The higher repulsion energy of a second electron entering 3d makes it unfavorable compared with the second electron entering 4s.

Answer 2

$\rightarrow\huge\text{Answer}$

Scandium has three valence electrons. The aufbau principle tells us they should add to the lowest available energy sublevel. Therefore, the first electron goes into 3d. ... The higher repulsion energy of a second electron entering 3d makes it unfavorable compared with the second electron entering 4s.