Ozone, O3, acts as filter of harmful UV radiation in the stratosphere by absorbing light with a wavelength of 290 nm. The photon at 290 nm causes an O-O bond in O3 to give O2 and O.
a) Draw Lewis resonance structures of Ozone molecule
b) Photons from wavelength 290 nm have sufficient energy for O3 --> O2 + O., but to break O2 requires photons with only wavelength 210 nm. Explain your answer, briefly.