If you put 120 volts of electricity through a pickle, the pickle will smoke and start glowing orange-yellow. The light is emitted because sodium ions in the pickle become excited; their return to the ground state results in light emission.
(a) The wavelength of this emitted light is 589 nm. Calculate its frequency.
(b) What is the energy of 0.10 mole of these photons?
(c) Calculate the energy gap between the excited and ground states for the sodium ion.