The total number of electrons in all orbitals having principal quantum number $n = 2$ and azimuthal quantum number $l = 1$ is ..........

The number of valence electrons in one mole of nitride ion is ............ mole.

How is the angular node determined? State the number of angular nodes for $s, p, d,$ and $f$ orbitals.

If the $n^{th}$ specific period of the periodic table contains $\frac{(n+2)^2}{2}$ elements,then the maximum value of the azimuthal quantum number associated with that period is:

Identify an orbital with the quantum numbers $n=4, \ell=3, m=0$.

The number of orbitals associated with quantum numbers $n=5, m_s=+\frac{1}{2}$ is