Which refrigerants have replaced CFCs?

• A. Hydrocarbons (HCs)
• B. Hydrofluorocarbons (HFCs)
• C. Azole mixtures
• D. Chlorinated solvents

Answer: (B)

Hydrofluorocarbons (HFCs) have replaced chlorofluorocarbons (CFCs) due to their lower ozone-depleting potential. CFCs contributed to the depletion of the ozone layer and were phased out under international agreements like the Montreal Protocol. HFCs, while still potent greenhouse gases, do not contain chlorine and therefore do not harm the ozone layer. They are used in various applications such as refrigeration and air conditioning, providing effective cooling without the ozone-depleting properties associated with CFCs.

Other options do not serve as replacements for CFCs. Hydrocarbons (HCs) are considered natural refrigerants and can be used instead, but they are not a direct replacement for CFCs like HFCs. Azole mixtures and chlorinated solvents are not commonly used as refrigerants, making them unsuitable comparisons in this context. The focus on HFCs highlights their role in continuing refrigeration and air conditioning technology while adhering to the regulations stemming from the environmental impact of substances like CFCs.