CoreDifficulty 2/5
Ranked from highest ozone depletion potential to lowest, how do CFCs, HCFCs and HFCs compare?
- AHCFCs are highest, CFCs are lower, and HFCs have none because they lack fluorine
- BHFCs are highest, CFCs are lower, and HCFCs have none because they lack bromine
- CAll three are equal, because each contains a halogen that reaches the stratosphere
- DCFCs are highest, HCFCs are lower, and HFCs have none because they lack chlorine
Show answer and rationale
Correct: D. Chlorine is what destroys stratospheric ozone. CFCs carry the most, HCFCs carry less because hydrogen makes them break down lower in the atmosphere, and HFCs carry none at all.
- A — The order is inverted, and fluorine is not the ozone-depleting element in these compounds.
- B — HFCs have an ozone depletion potential of zero, and bromine is not present in any of the three.
- C — They are not equal; the whole point of the HCFC and HFC transitions was to lower the potential.