Question

In the Aufbau order of occupancy of electronic energy levels, the level occupied just after 4p is...

Answer 1

Answer;

5s

Step-by-step explanation;

• According to the Aufbau principle in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels.
• The Aufbau order of occupancy of electronic energy levels is:

1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s etc.

• From this we can see that the level occupied just after 4p is 5s , such that 5s is of a higher energy level compared to 4s