What class of chemicals is responsible for ozone depletion?methanephotochemical smogcarbon dioxidechlorofluorocarbon

The class of chemicals responsible for ozone depletion is chlorofluorocarbons (CFCs). CFCs are man-made compounds that were once commonly used in refrigeration, aerosol propellants, and solvent cleaning. When released into the atmosphere, CFCs eventually reach the stratosphere, where they are broken down by ultraviolet (UV) radiation, releasing chlorine atoms. These chlorine atoms can then react with ozone (O₃) molecules, leading to the thinning of the ozone layer. This depletion of ozone is concerning because the ozone layer protects the Earth from harmful UV radiation, which can lead to increased skin cancer rates, cataracts, and other environmental impacts.

In contrast, while methane and carbon dioxide are significant greenhouse gases contributing to global warming, they do not play a direct role in ozone depletion. Photochemical smog is a result of reactions between sunlight and pollutants but is not directly related to ozone layer depletion in the same way that CFCs are.