A hydrogen atom in a state having a binding energy (this is the energy required to remove an electron) of 0.85 eV makes a transition to a state with an excitation energy (this is the difference in energy between the state and the ground state) of 10.2 eV.
(a) Find the energy of the emitted photon.
(b) Show this transition on an energy-level diagram for hydrogen, labeling the appropriate quantum numbers.