Introduction
There are environmental chemical processes which require light to react. These processes are called photochemical reactions. Photochemical reaction is commonly initiated due to the absorption of solar energy or light. When molecules absorb energy in the form of light, the atoms are converted in a transient excited state (Larson & Weber, 1994). This transition state or excited has completely different physical and chemical properties with the initial state of the molecule. The excited states also have more tendencies to react since they are considered stronger acids and stronger reductants that the initial state of the molecule. The excited state of ...
