The energy (in $eV$) required to excite an electron from $n=2$ to $n=4$ state in a hydrogen atom is:

Which fact indicates that the total energy of an electron in an atom is negative?

The ionisation potential of a hydrogen atom is $13.6 \, V$. The energy required to remove an electron in the $n = 2$ state of the hydrogen atom is.....$eV$.

The ratio of energies of photons produced due to the transition of an electron in a hydrogen atom from its $(i)$ $3^{\text{rd}}$ to $2^{\text{nd}}$ energy level and (ii) highest energy level to $3^{\text{rd}}$ level is:

In the $n^{th}$ orbit,the energy of an electron is given by $E_n = -\frac{13.6}{n^2} \text{ eV}$ for a hydrogen atom. The energy required to excite the electron from the first orbit $(n=1)$ to the second orbit $(n=2)$ will be..... eV.

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