Which claim about CFCs is false?

CFCs, or chlorofluorocarbons, are indeed light molecules that rise in the atmosphere. This characteristic allows them to reach the stratosphere, where they can cause damage to the ozone layer. Once in the stratosphere, CFCs can remain for an extended period, hence they have long atmospheric lifetimes. Additionally, CFCs are known to significantly contribute to ozone depletion because UV radiation breaks them down, releasing chlorine atoms that catalyze the destruction of ozone molecules.

The claim that CFCs are heavy molecules that will sink in the atmosphere contradicts their actual properties. Instead, they possess lower density than air, allowing them to ascend rather than sink. Understanding this attribute is crucial when discussing their behavior in the atmosphere and their environmental impact, particularly regarding ozone layer depletion.