(a) How many sub-shells are associated with n = 4?
(b) How many electrons will be present in the sub-shells having ms value of –1/2 for n = 4?
(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 nth shell = n2
For n = 4
Number of orbitals = 16
Each orbital has one electron with ms = -1/2
Hence there will be 16 electrons with ms = -1/2
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