Final answer:
The statement that one electron occupies each orbital until all orbitals contain one electron with the same spin when orbitals are of equal energy is true, following Hund's Rule and the principles of electron configuration and electron-electron repulsion.
Step-by-step explanation:
The statement is true. According to Hund's Rule, when electrons are added to orbitals of equal energy, one electron enters each orbital until all the orbitals contain one electron with the same spin direction. This rule is a consequence of electron-electron repulsion, where electrons will avoid pairing in an orbital as long as there are empty orbitals available in the same sublevel.
Electron configuration follows a specific order, starting from the orbitals closest to the nucleus (which have the lowest energy) and then filling orbitals of increasing energy levels further from the nucleus. This principle, along with the Pauli exclusion principle, emphasizes that no two electrons can have the same set of quantum numbers within an atom, meaning they must have opposite spins if they occupy the same orbital.
Furthermore, each orbital can hold a maximum of two electrons, and these electrons will occupy orbitals with the lowest possible energy first. Therefore, the trend of filling lower energy orbitals before moving to higher ones is followed, in accordance with the principles of energetic stability and atomic structure.