The energy of the second excited state of the $Li^{2+}$ ion is ............... $eV$.

Match the principles given in List-$I$ with their discoverers given in List-$II$.

List-$I$	List-$II$
$(1)$ Exclusion Principle	$(A)$ Hund
$(2)$ Multiplicity Rule	$(B)$ Heisenberg
$(3)$ Uncertainty Principle	$(C)$ Einstein
$(4)$ Quantum Theory	$(D)$ Planck
	$(E)$ Pauli

In an atom,two electrons move around the nucleus in circular orbits of radii $R$ and $4R$. The ratio of the time taken by them to complete one revolution is

First and second excitation potentials of hydrogen atom (in $eV$) would be respectively

The angular momentum of an electron in an $H$ atom in a particular $n$ state is $\frac{h}{\pi}$. What is the energy in $J$ required to excite the electron from this particular $n$ state to $(n+1)$ state? $(x = 2.18 \times 10^{-18} \ J)$

In the hydrogen atomic spectrum,a series limit is found at $12186.3 \ cm^{-1}$. To which series does it belong?