What is the total energy of an electron at an infinite distance from the nucleus in an atom?

$\frac{x}{x+4}$ is the ratio of energies of photons produced due to the transition of an electron of a hydrogen atom from its $(i)$ third permitted energy level to the second level and $(ii)$ the highest permitted energy level to the second permitted level. The value of $x$ will be.

Energy of $H$-atom in the ground state is $-13.6 \; eV$. The energy needed to ionize a hydrogen atom which is in its second excited state is ....... $eV$.

In a hydrogen atom,the electron makes a transition from the $(n+1)^{\text{th}}$ level to the $n^{\text{th}}$ level. If $n >> 1$,the frequency of the radiation emitted is proportional to:

Find the ratio of energies of photons produced due to the transition of an electron in a hydrogen atom from its $(i)$ second permitted energy level to the first level,and $(ii)$ the highest permitted energy level to the first permitted level.

As the quantum number $n$ increases,the difference in energy between consecutive energy levels