IB ESS HL 6.4.12 HFCs Question Bank
Practise IB ESS HL 006.004.012 by applying hfcs concepts to exam-style environmental systems questions.
- Syllabus
- First assessment 2026
- Course
- ESS HL
- Level
- HL
Practise IB ESS HL 006.004.012 by applying hfcs concepts to exam-style environmental systems questions.

Figure:Comparison of the effects of CFCs, HCFCs and HFCs

Figure:HCFCs and HFCs cause less damage than CFCs but still affect the environment
The hole in the ozone layer over Antarctica, discovered in the 1980s, was caused by chlorofluorocarbons (CFCs). The Montreal Protocol requires the use of hydrochlorofluorocarbons (HCFCs) or hydrofluorocarbons (HFCs) instead of CFCs (Figure: Comparison of the effects of CFCs, HCFCs and HFCs). However, these two gases are also linked to environmental problems (Figure: HCFCs and HFCs cause less damage than CFCs but still affect the environment).
Outline why governments agreed to phase out the use of HFCs from 2019 in the Kigali Amendment to the Montreal Protocol.
because HFCs are bad for climate/contribute to global warming; realisation that environmental issues need to be addressed at an intergovernmental level; realisation that changes in behaviour are necessary to protect the environment in the future; in response to development in scientific understanding of issue; rich countries agreed to provide financial assistance for poorer countries to phase out HFCs; because technological development has found alternatives to HFCs;