Chemistry - GENERAL CHEMISTRY Question with Solution | TestHub

When $n=3,l=0,1,2$ i.e., there are $3s,3p$ and $3d$ orbitals. If all these orbitals are completely occupied as
$$\text{ Total }18\text{ electrons, }9\text{ electrons with }s=+\frac{1}{2}\text{ and }9\text{ with }s=-\frac{1}{2}.$$ Alternatively In any $n$th orbit, there can be a maximum of $2n^2$ electrons. Hence, when $n=3$, number of maximum electrons $=18$. Out of these 18 electrons, 9 can have spin $-\frac{1}{2}$ and remaining nine with spin $=+\frac{1}{2}$.