Aufbau

[Sukanya Mohapatra 2G]

Can someone explain the Aufbau Principle in greater detail?

[Cooper Baddley 1F]

The Aufbau principle states that you start filling the lower energy subshells before continuing on to the ones with the higher energy. So for example you wouldn't start filling up 2p before filling 2s

[Alice Chang 2H]

Here's some info I found by a Google search online here: https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Electronic_Structure_of_Atoms_and_Molecules/Electronic_Configurations/Aufbau_Principle

Aufbau comes from the German word "Aufbauen" which means "to build". In essence when writing electron configurations we are building up electron orbitals as we proceed from atom to atom. As we write the electron configuration for an atom, we will fill the orbitals in order of increasing atomic number. The Aufbau principle originates from the Pauli’s exclusion principle which says that no two fermions (e.g., electrons) in an atom can have the same set of quantum numbers, hence they have to "pile up" or "build up" into higher energy levels. How the electrons build up is a topic of electron configurations.

Though I find this video to be more helpful visually, although they never specifically say it's the Aufbau principle:
https://www.khanacademy.org/science/chemistry/electronic-structure-of-atoms/electron-configurations-jay-sal/v/electron-configurations-2

There's also some videos online that may help explain it further. Hope this helps somehow!

[805422680]

The Aufbau Principle states that the orbitals with the lower energy level get filled with electrons before the higher energy level. Thus, this gives us information about the electronic configuration of the atom.