The ground state energy of a hydrogen atom is $-13.6 \, eV$. When its electron is in the first excited state,its excitation energy is ...... $eV$.

If the energy of an electron in the first Bohr orbit of the $H$-atom is $-2.18 \times 10^{-18} \text{ J}$, then the energy of the electron in the second orbit will be:

$A$ photon is emitted in transition from $n = 4$ to $n = 1$ level in a hydrogen atom. The corresponding wavelength for this transition is $......... \, nm$ (given,$h = 4 \times 10^{-15} \, eV \cdot s$ and $c = 3 \times 10^8 \, m/s$):

The maximum wavelength of incident radiation required to ionize a hydrogen atom in its ground state is nearly

If the ionisation energy for the hydrogen atom is $13.6$ eV, then the energy required to excite it from the ground state to the next higher state is nearly (in $eV$)

The following diagram indicates the energy levels of a certain atom. When the system moves from the $2E$ level to the $E$ level,a photon of wavelength $\lambda$ is emitted. The wavelength of the photon produced during its transition from the $\frac{4E}{3}$ level to the $E$ level is