A highly reactive diatomic molecule is generated through photochemical decomposition of chlorinated hydrocarbons by ultraviolet radiation. This process involves the breaking of chemical bonds within the chlorinated compound due to the absorption of UV photons, resulting in the formation of this potent oxidizing agent. A common example includes the breakdown of chlorofluorocarbons (CFCs) in the upper atmosphere, leading to the release of chlorine atoms, which then combine to form the diatomic molecule.
The presence of this molecule in the stratosphere is crucial due to its significant impact on ozone depletion. As a powerful oxidizing agent, it readily reacts with ozone (O3), converting it into molecular oxygen (O2). This depletion reduces the atmosphere’s ability to filter harmful ultraviolet radiation from the sun, increasing the risk of skin cancer and other adverse health effects. Historically, the widespread use of CFCs in refrigerants and aerosols led to significant increases in its concentration in the atmosphere, prompting international agreements like the Montreal Protocol to phase out these ozone-depleting substances.
