Answer: 124eV
Explanation: Apply Planck - Einstein Relation to calculate the energy of an X-Ray photon that has a frequency of 3.00 x 10^16 Hz and the energy of a photon is proportional to its frequency
E= hv
where E - the energy of the photon
h - Planck's constant, equal to 6.626 x 10^-34 Js
v - the frequency of the photon
and 1 Hz is equal to 1 s^-1
Thus E= 1.988 x 10^-17J
Now convert the energy of photon from joules to eV
Therefore we get 1.988 x 10^-17J x ( 1 eV / 1.6022 x 10^-19 J)
= 124 eV.
