The ground state energy of hydrogen atom is -$\displaystyle 13.6$ eV . What is the potential energy and kinetic energy of an electron in the third excited state?

\[\begin{array}{|ll|} \hline \text { Calculation of potential energy of electron } & 1 \\ \text { Calculation of kinetic energy of electron } & 1 \\ \hline \end{array} \] For third excited state \(\displaystyle \mathrm{n}=4\) \[\mathrm{E}_{4}=\frac{-13.6}{4^{2}}=\frac{-13.6}{16}=-0.85 \mathrm{eV} \] Potential Energy \(\displaystyle =2 \times\) Total Energy \(\displaystyle =2 \times \mathrm{E}_{4}\) \[\begin{aligned} & =2 \times(-0.85) \mathrm{eV} \\ & =-1.70 \mathrm{eV} \end{aligned} \] Kinetic energy \(\displaystyle =-(\) Total Energy \(\displaystyle )=-\mathrm{E}_{4}\) \[=0.85 \mathrm{eV} \]