The Energy of the Nth Level in a One-Electron Atom $\times$

Multiple Choice

The energy of the nth level in a one-electron atom is E_n = -13.6(Z²/n²) eV.Consider a beryllium ion with all but one of its electrons removed (a beryllium atom normally has four electrons) .What is the wavelength of a photon emitted when the electron makes the transition from the third-lowest to the lowest energy state?

A) 1.03 $\times$ 10^-7 m
B) 2.03 $\times$ 10^-8 m
C) 6.43 $\times$ 10^-9 m
D) 5.71 $\times$ 10^-9 m
E) 1.03 $\times$ 10^-27 m