The wave function for the first excited state of hydrogen \(n=2, \ell=0\) is

\[\psi(r)=\frac{1}{4 \sqrt{2 a_{0}^{3} \pi}}\left(2-\frac{r}{a_{0}}ight) e^{-\frac{r}{2 a_{0}}}\]

Take the reduced mass to be \(\approx m_{e}\).

Use Schrödinger's wave equation to calculate the energy of this state.