Question

(a) How many subshells are associated with n = 4 ? (b) How many electrons will be present in the subshells having ms value of $-\frac{1}{2}$ for n = 4 ?

Answer 1

(a) n = 4 (Given) For a given value of 'n', 'l' can have values from zero to (n =1).
∴ l = 0, 1, 2, 3 Thus, four sub-shells are associated with n = 4, which are s, p, d and f
(b) Number of orbitals in the n th shell = n 2 For n = 4 Number of orbitals = 16
If each orbital is taken fully, then it will have 1 electron with a ms value of $-\frac{1}{2}$
∴ Number of electrons with ms value of ($-\frac{1}{2}$) is 16