For this problem, the applicable equation is that derived by Max Planck
E = h * frequency where E is the energy of the photon, and h is the Planck’s constant which has a value of 6.626 x [tex] 10^{-34} [/tex] J-s.
Upon substituting,
5.53 x [tex] 10^{-17} [/tex] J = 6.626 x [tex] 10^{-34} [/tex] J-s * frequency
Frequency = 8.35 x [tex] 10^{16} [/tex] [tex] s^{-1} [/tex]
The answer is 8.35 x [tex] 10^{16} [/tex] [tex] s^{-1} [/tex].