Aufbau principle: Learn the definition of

Learn the definition of the Aufbau Principle , how to apply the Aufbau rule for electrons, and where exceptions occur in the periodic table. The Aufbau principle is a fundamental concept in quantum chemistry and atomic physics that explains how electrons are distributed in an atom’s orbitals. The term “ Aufbau ” is a German word which means “building up” or “construction”. Learn how to use the Aufbau principle to construct the electron configuration of atoms in their ground state. The principle states that electrons fill the lowest energy subshells first, according to the sum of their quantum numbers.