"Electrons added to atomic orbitals of the same energy will remain unpaired with parallel spins until the subshell is more than half-filled" is a statement of
A)the aufbau principle.
B)Hund's rule.
C)the Pauli exclusion principle.
D)the periodic law.
E)the singularity rule.

Question

Quizplus · Accepted Answer

This statement is a restatement of Hund's rule, which states that electrons will occupy unpaired orbitals of the same energy level with parallel spins before they begin to pair up. This is because the electrostatic repulsion between electrons in the same orbital is minimized when their spins are parallel. Once all the orbitals of a subshell are half-filled, the repulsion between electrons is greater than the repulsion between electrons and the nucleus, and the electrons begin to pair up.

"Electrons Added to Atomic Orbitals of the Same Energy Will