A photon of energy 12.09 eV is absorbed by a hydrogen atom in its ground state. The electron will be

Question

A photon of energy 12.09 eV is absorbed by a hydrogen atom in its ground state. The electron will be excited to the state with principal quantum number:

Professor PC Thomas Classes · Answer

The final energy is $-13.6 + 12.09 = -1.51$ eV. Since $E_n = -13.6/n^2$, solving $-1.51 = -13.6/n^2$ gives $n = 3$.