Question

What would you predict for the atomic number of the noble gas beyond $Rn$, if such an element has sufficient stability to be prepared or observed ? Assume that $g-$orbitals are still not occupied in the ground state of preceding elements.

Answer 1

Atomic Number would be $118$. Electronic configuration of $Rn$ is $4f^{14}5d^{10}6s^{2}6p^6.$ The nodle gas beyond $Rn$ should have electronic configuration $5f^{14}6d^{10}7s^{2}7p^6$, according to Afbous principle. Above electronic configuration corresponds to atomic number $118$.