Question

In what order do electrons fill orbitals?

A. Before pairing, 1 electron occupies each s and p orbital.
B. The p orbitals fill before the sorbitals in an energy level.
C. Electrons fill orbitals in order of increasing orbital energy.
D. Orbitals s, p, and then d fill in one energy level before starting the
next level.

Answer 1

C. Electrons fill orbitals in order of increasing orbital energy.