The kinetic energy of an electron in the $n^{th}$ orbit of a hydrogen-like species with atomic number $Z$ is $13.6 \frac{Z^2}{n^2} \ eV$. The potential energy of this electron in the same orbit will be:

The energy of the highest energy photon of the Balmer series of the hydrogen spectrum is close to $... eV$.

The binding energy of a hydrogen atom in the ground state is $13.6 \ eV$. The energies required to remove an electron from the first three energy levels of the hydrogen atom are,respectively,(in $eV$):

As an electron makes a transition from an excited state to the ground state of a hydrogen-like atom/ion:

If an electron in the excited state falls to the ground state,a photon of energy $5 \ eV$ is emitted. The wavelength of the photon is nearly: (in $nm$)

Assertion : Between any two given energy levels,the number of absorption transitions is always less than the number of emission transitions.
Reason : Absorption transitions start from the lowest energy level only and may end at any higher energy level. But emission transitions may start from any higher energy level and end at any energy level below it.