Which highly toxic gas can form when R-22 contacts a torch flame?
Safety · EPA 608 Type I. The correct answer, and the reasoning behind it.
Decomposition products of refrigerants at high temperatures, and safe handling.
The question
Which highly toxic gas can form when R-22 contacts a torch flame?
- Ammonia
- Hydrogen sulfide
- Nitrous oxide
- PhosgeneCorrect answer
Why “Phosgene” is correct
R-22 contains chlorine, and at flame temperatures chlorine-containing refrigerants can form phosgene, a highly toxic gas. Hydrochloric and hydrofluoric acids form as well.
Source: EPA: Test Topics
Why the other answers are wrong
- Ammonia — Ammonia is a refrigerant in its own right and is not formed from R-22.
- Hydrogen sulfide — R-22 contains no sulfur, so it cannot form hydrogen sulfide.
- Nitrous oxide — R-22 contains no nitrogen, so it cannot form nitrous oxide.
Practice more of this
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