The mechanism by which chlorofluorocarbons CFCs break down ozone molecules in the stratosphere involves a series of chemical reactions. Here is a simplified explanation of the process:1. CFCs are released into the atmosphere from various sources, such as refrigeration systems, air conditioners, and aerosol sprays. They are stable and non-reactive in the lower atmosphere, allowing them to persist and eventually reach the stratosphere.2. In the stratosphere, CFCs are exposed to high-energy ultraviolet UV radiation from the sun. This UV radiation causes the CFC molecules to break apart, releasing highly reactive chlorine atoms. The reaction can be represented as: CFC + UV radiation Cl + other products where Cl represents a reactive chlorine atom 3. The reactive chlorine atoms then react with ozone O3 molecules, breaking them down into oxygen molecules O2 and chlorine monoxide ClO . This reaction can be represented as: Cl + O3 ClO + O24. The chlorine monoxide ClO molecule can then react with another ozone molecule, releasing an oxygen molecule and regenerating the reactive chlorine atom: ClO + O3 Cl + 2 O25. The reactive chlorine atom can then continue to participate in the breakdown of more ozone molecules, initiating a chain reaction that can destroy thousands of ozone molecules before the chlorine atom is eventually removed from the atmosphere by other chemical reactions.This mechanism of CFCs breaking down ozone molecules in the stratosphere leads to the depletion of the ozone layer, which is essential for protecting life on Earth from harmful UV radiation.