Question

Find the energy of an electron in the n = 2 state of hydrogen.
eV

If this electron undergoes a transition to the ground state, what is the energy, in electron-volts, of the photon that is emitted?
eV

Answer 1

(a).The energy of an electron in the n = 2 state of hydrogen = -13.6 eV / n ²

                                                                                                = -13.6 eV / 2 ²

                                                                                            E = -3.4 eV

b)

Ground state energy E ' = -13.6 eV

Emitted photon energy = E - E '

                                   = 10.2 eV