Chapter 7, Problem 32QP

A hydrogen-like ion is an ion containing only one electron. The energies of the electron in a hydrogen-like ion are given by

$En\text{ = }-\text{(2}\text{.18 }\times {\text{ 10}}^{\text{-18}}\text{ J) }{Z}^{\text{2}}\left(\frac{1}{n^2}\right)$

where n is the principal quantum number and Z is the atomic number of the element. Calculate the ionization energy (in kJ/mol) of the He* ion.