We applied the Bohr model to hydrogen, but it can be extended to treat ions with one electron such as He⁺ and Li⁺². Follow the derivation in Equations 29.10 through 29.15, but now let the nucleus have a charge +Ze (for a nucleus with atomic number Z containing Z protons) instead of just +e (a single proton). Derive an expression for the energy of the ground state of the ion. Compare your result for the ionization energy of He with the measured value of approximately 54 eV.