METO 621. Lesson 20. Photochemical Change. A quantum of radiative energy is called a photon, and is given the symbol h n . Hence in a chemical equation we write: O 3 + h n → O 2 + O The energy of a photon in terms of its wavelength l is E=119625/ l kJ mol -1 or 1239.8/ l eV
O3 + hn →O2 + O
AB + hn→AB*
O3 + hn → O2 + O
O3 + hn → O2(1Dg) + O(1D)
O(1D) + H2O → OH + OH
A + BC → ABC* → AB + C
A + B → products
proceeds at a rate proportional to the concentrations raised to some power
The partition functions may each have a different temperature dependence but the over all temperature dependence can be expressed as a power law.
Where A’ is the temperature-independent part of the pre-exponential function, and n is the exponent for the temperature dependence.