As the electron is ejected, so it makes a transition from its ground state n=1 to the immediate excited state m=2.

Thus the energy associated will be,

The energy is in this term because the question says that the electron ejects when a photon of frequency 228Å is applied.

Now comparing this energy with that of the orbital energy, we get,

1.6 is multiplied as because the energy of the photon is in electron-volt.So we multiplied the charge of the electron.

Hence, the ion may be