Aphoton with a frequency of 5.48 × 10^14 hertz is emitted when an electron in a
mercury atom falls to a lower energy level.
determine the energy of this photon in electronvolts.

     The energy of an eletromagnetic wave is given by the Planck's Equation:


 
     Entering the unknowns:


 
     Converting unit:



Obs: approximate results

If you notice any mistake in my english, please let me know, because i am not native.