Energy of a photon is 1.5 eV/atom. The wavelength of the photon is equal to
8266nm
82.66nm
82660nm
826.6nm
E=hCλ; E=1.5 ev/atom; 1.5×1.602×10-19J=6.625×10-34J×3×108m/sλ; λ=8.26×10-7m=826.6 nm; or λ(nm)=1240E(ev/atom)