Final answer:
The correct order in which electron levels get filled is S, P, D, F, following the lowest energy orbitals first. The filling order, confirmed by experimental and theoretical calculations, is crucial to understanding the periodic table and element properties.
Step-by-step explanation:
The correct order in which levels get filled with electrons is S, P, D, F. This is based on the order of energy levels and sublevels within an atom, where electrons occupy the lowest energy orbitals available first. The comprehensive order for filling the orbitals with electrons follows this sequence: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, and so on.
As an example, for the element tin (Sn), which has 50 electrons, the electron configuration would be predicted by following this order until all 50 electrons are accounted for. The actual configuration for tin would be [Kr] 5s24d105p2.
Understanding this order is important for comprehending the structure of the periodic table and the properties of elements, such as their electronegativity and chemical behaviors.