Physics - Modern Physics Question with Solution | TestHub

We know that total energy of electron in hydrogen atom is given by $E_{\eta }=\frac{-13.6}{n^2}$ Also, total energy of electron in second excited state $=\frac{-13.6}{(3{)}^2}=-1.51\mathrm{eV}$ $\Rightarrow$ lonization energy or energy required to ionize hydrogen atom from its second excited state $=1.51\mathrm{eV}$