Which statement is true about R-12 and R-11?

Which statement is true about R-12 and R-11?

• A. They are HCFCs
• B. They are HFOs
• C. They are HFCs
• D. They are CFCs

Answer: (D)

R-12 and R-11 are chlorofluorocarbons, meaning they are CFCs. Their molecules contain chlorine, fluorine, and carbon, and the chlorine in these compounds releases ozone-depleting chlorine radicals when exposed to sunlight in the atmosphere. That makes them highly destructive to the ozone layer, which is why they were phased out under international agreements. They’re not HCFCs (which include hydrogen and are somewhat less ozone-depleting), not HFCs (which have no chlorine), and not HFOs (a newer class with different chemistry). In short, R-12 and R-11 are CFCs—the ozone-depleting refrigerants from earlier eras.

R-12 and R-11 are chlorofluorocarbons, meaning they are CFCs. Their molecules contain chlorine, fluorine, and carbon, and the chlorine in these compounds releases ozone-depleting chlorine radicals when exposed to sunlight in the atmosphere. That makes them highly destructive to the ozone layer, which is why they were phased out under international agreements. They’re not HCFCs (which include hydrogen and are somewhat less ozone-depleting), not HFCs (which have no chlorine), and not HFOs (a newer class with different chemistry). In short, R-12 and R-11 are CFCs—the ozone-depleting refrigerants from earlier eras.