Which principle asserts that no two electrons in the same atom can have the same set of four quantum numbers?

The Pauli Exclusion Principle states that no two electrons in the same atom can have the same set of four quantum numbers. Each electron in an atom is described by a unique combination of quantum numbers, which include the principal quantum number, azimuthal quantum number, magnetic quantum number, and spin quantum number. This principle is critical for understanding the arrangement of electrons in atoms and helps dictate the structure of the periodic table.

When electrons occupy the same orbital, they must have opposite spins, which ensures that each electron is distinguishable from the others. This distinct identification is essential for the stability of atoms and influences their chemical behavior. The principle is a fundamental concept in quantum mechanics and underpins much of atomic structure theory.

In contrast, the Aufbau Principle describes the order in which electrons fill orbitals, starting from the lowest energy level and moving to higher ones. Hund's Rule pertains to the way electrons populate degenerate orbitals, ensuring maximum spin multiplicity. The Quantum Mechanical Model encompasses the principles of quantum mechanics as a whole, including but not limited to the Pauli Exclusion Principle.