Noble gases are known for their stable electronic configurations, which typically involve completely filled s and p orbitals. These elements, including helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn), have closed electron shells and exhibit minimal reactivity.
To clarify, the noble gases do not have f or d orbitals filled in their ground state electronic configurations. The f orbitals are found in the fourth energy level (principal quantum number n = 4) and beyond, while the d orbitals are present in the third energy level (principal quantum number n = 3) and beyond. The noble gases, with their completely filled s and p orbitals, do not have electrons in the higher-energy f or d orbitals.
To achieve stability, atoms generally strive to fill their outermost energy level or shell, known as the valence shell. For the noble gases, this is achieved by completely filling the s and p orbitals in their respective energy levels. These orbitals can accommodate a maximum of two electrons for the s orbital and six electrons for the p orbital.
If a hypothetical noble gas were to have more electrons, it would likely involve filling the f and d orbitals. This would imply that the energy level corresponding to the f orbitals (n = 4 or higher) or the d orbitals (n = 3 or higher) would become the outermost energy level or shell. However, no such noble gas has been discovered or synthesized.
It's important to note that the stability of an element is not solely determined by filling the p orbital. The overall stability depends on various factors, including the balance of attractive and repulsive forces between electrons and the nucleus, the ability to achieve a low-energy configuration, and the fulfillment of the octet rule (for elements in the first three periods) or the duet rule (for hydrogen and helium).