How many moles of carbon atoms, C, contain the same number of atoms as
(a) 1 mole of copper atoms, Cu,
(b) 2.5 moles of magnesium atoms, Mg, and
(c) 0.13 mole of sulfur atoms, S?

There is one s orbital, and there are three p orbitals, five d orbitals, and seven f orbitals. thus, the answer is b. do not confuse the number of orbitals in a subshell with the number of electrons the subshell can hold. each orbital can hold two electrons, so the capacity of an nf subshell is 14 electrons.

High-energy and unstable.