The number of radial nodes of $3s$ and $2p$ orbitals are respectively.

Which of the following statements is true regarding the hydrogen atom?

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

The graph showing the variation of probability density,$\psi^2(r)$ with the distance of the electron from the nucleus,$r$ is given below. This represents:

The probability of finding an electron in the $p_x$ orbital is

"Pairing of electrons in the orbitals belonging to the same subshell does not occur unless each orbital belonging to that subshell has got one electron each." This statement is known as