Question

To prevent electron repulsion when filling orbitals, what rule states that electrons prefer to have their own orbital before being forced to double up with another electron? a. Pauli Exclusion Principle

b. Hund's Rule
c. Aufbau Principle
d. Heisenberg Uncertainty Principle

Answer 1

Hund's Rule is the principle stating that electrons will singly occupy degenerate orbitals before any are doubly occupied to minimize repulsion.

Step-by-step explanation:

The rule that states electrons prefer to occupy their own orbital before pairing up in the same orbital to minimize electron repulsion is known as Hund's Rule. According to Hund's Rule, when electrons are placed in degenerate orbitals (orbitals that have the same energy level within a subshell), they must first singly occupy each orbital with parallel spins before any orbital can be doubly occupied. This rule works in concert with the Pauli Exclusion Principle, which mandates that no two electrons can have the same set of quantum numbers, implying that when two electrons occupy the same orbital, they must have opposite spins. The Aufbau Principle dictates that electrons fill the lowest-energy orbitals first. These principles together describe how electrons are distributed in an atom's orbitals.