निम्नलिखित पर विचार कीजिए :
- 1.ऐरोसॉल
- 2.फोम एजेंट
- 3.अग्निमंदक
- 4.स्नेहक (लूब्रिकेंट)
उपर्युक्त में से कितनों को बनाने में हाइड्रोफ्लुओरोकार्बन प्रयुक्त होते हैं?
Read this question in English
Consider the following:
1. Aerosols
2. Foam agents
3. Fire retardants
4. Lubricants
In the making of how many of the above are hydrofluorocarbons used?
(a) Only one · (b) Only two · (c) Only three · (d) All four
उत्तर और व्याख्या · explanation in English
Answer: (c) केवल तीन
Hydrofluorocarbons (HFCs) replaced ozone-depleting CFCs and HCFCs in cooling, aerosol propellants, foam blowing and fire suppression. Lubricants are not an HFC application, so three of the four are correct.
- ✓ 1. HFCs serve as propellants in aerosol cans, one of the uses listed by the US EPA and UNEP.
- ✓ 2. HFCs are used as blowing agents to make insulating and other foams.
- ✓ 3. Some HFCs are used as fire-suppression (fire-extinguishing) agents, a replacement for ozone-depleting halons.
- ✗ 4. Lubricants are oils and greases; HFCs are gases used as refrigerants, propellants, blowing agents and fire suppressants, not as lubricants.
Remember · HFCs: refrigerants, AC, aerosols, foam blowing, fire suppression, solvents. Not ozone-depleting but potent greenhouse gases; phased down under the Kigali Amendment (2016).
Sources
- US EPA, Background on HFCs and the AIM Act ↗ “HFCs are used in applications such as air conditioning, refrigeration, fire suppression, solvents, foam blowing agents, and aerosols.”
- UNEP OzonAction, About the Montreal Protocol ↗ “HFCs are now widespread in air conditioners, refrigerators, aerosols, foams and other products. While these chemicals do not deplete the stratospheric ozone layer, some of them have high GWPs ranging from 12 to 14,000.”
Question and answer: UPSC's official GS Paper I (2023, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·