The outermost electron of an atom has a binding energy of 2.5 eV. The atom is exposed to light of a high enough frequency to cause exactly one electron to be ejected. The ejected electron is found to have a KE of 2.0 eV. 23. How much energy did photons of the incoming light contain? A) 0.50 eV B) 0.80 eV C) 4.5 eV D) 5.0 eV