Energy of electron, when it is present at infinite distance from the nucleus is

Energy is represented by the for${\mathrm{E}}_{\mathrm{n}}={\mathrm{E}}_1\times \frac{{\mathrm{Z}}^2}{{\mathrm{n}}^2}$for hydrogen-like species. ${\mathrm{E}}_1$ is the energy for the hydrogen first orbit and has a negative value. As the n increases, energy increases i.e., it becomes less negative. When $\mathrm{n}=\mathrm{\infty }$, the electron can have a maximum energy value of zero.