a. How many sub-shell are associated with `n = 4`?
b. How many electron will be present in the sub-shelll having `m_(s)` value of `-1//2` for `n = 4`?

Answer

A

Explanation

a. For `n = 4,l` can have value `0,1,2 ,3` Thus, there are four sub-shell in `s= 4` energy level These four sub-shell are `4s ,4p ,4d and 4f`
b. For the number orbital is `= (4)^(2) = 16` Each orbital can have one electron with `m_(s) = - 1//2` Thus, there are `16` electron in sub-shell having `n = 4` and `m_(s) = - 1//2`