How many electrons in an atom may have the following quantum numbers?
(1) n=4, `m_(S)=-(1)/(2)`
(2) n=3, l=0

Explanation

(1) For n=4, total number of electron
`=2n^(2)=2xx4^(2)=32`. Among these 32 electrons, half i.e. 16 electrons will have s or `m_(S)=+(1)/(2)` and the other 16 electrons will have `m_(S)=-(1)/(2)`.
(2) n=3, l=0 means 3s-subshell. Maximum number of electron in this subshell is two.