For an electron with $n = 3$,there is only one radial node. The orbital angular momentum of the electron will be

In an atom having $2$ $K$,$8$ $L$,$8$ $M$ and $2$ $N$ electrons,the number of electrons with $m=0$ and $s=+\frac{1}{2}$ is $:-$

Compare the energies of the following sets of quantum numbers for a multielectron system:
$A. n=4, \ell=1$
$B. n=4, \ell=2$
$C. n=3, \ell=1$
$D. n=3, \ell=2$
$E. n=4, \ell=0$
Choose the correct order of increasing energy from the options given below:

An ion has $18$ electrons in the outermost shell,it is

Which orbital is represented by the wave function $\Psi_{310}$?

Not considering the electronic spin,the degeneracy of the second excited state $(n=3)$ of $H$ atom is $9$,while the degeneracy of the second excited state of $H^{-}$ is