Question

The following ground-state electron configuration of potassium shows that for the ground state of the potassium atom the outermost electron is in a 4s state 1s^22s^22p^63s^23p^64s This tells you that, compared to the 3d level for this atom, the As level has a lower energy. has a higher energy. has approximately the same energy.

Answer 1

3d level of this potassium atom has higher energy than 4s. This is the reason that the outermost election is in a 4s state and not in 3d state.

The correct answer is "has lower energy".