*(a) 3F2: The maximum value of spin is = 1 here. This means there are 2 electrons. L = 3 so s and p electrons are ruled out. Thus the simplest possibility is d electrons. This is the correct choice for if we were considering f electrons, the maximum value of L allowed by Pauli principle will be L = 5 (maximum value of the magnitude of magnetic quantum number will be 3 + 2 = 5 .)**
Thus the atom has two d electrons in the unfilled shell.
*(b) 2P3/2 Here L=1, =1/2 and J=3/2**
Since J = L + , Hund’ rule implies the shell is more than half full. This means one electron less than a full shell. On the basis of ** picture it is easy to see that we have p electrons. Thus the atom has 5 p electrons.**
(c) 6S5/2 Here L = 0 . We either have five electrons or five holes. The angular part is antisymmetric. For five d electrons, the maximum value of the quantum number consistent with Pauli exclusion principle is ( 2 + 1 + 0 - 1 - 2 ) = 0 so L = 0 . For f or g electrons L > 0 whether the shell has five electrons or five holes. Thus the atom has five d electrons.
