Which of these refrigerants can form phosgene and hydrochloric acid when it decomposes in a 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 of these refrigerants can form phosgene and hydrochloric acid when it decomposes in a flame?
- R-12Correct answer
- R-134a
- R-600a
- R-744 (carbon dioxide)
Why “R-12” is correct
Phosgene and hydrochloric acid both contain chlorine, so only chlorine-containing refrigerants such as CFCs and HCFCs can form them. R-12 is a CFC, which makes it the one here.
Source: EPA: Test Topics
Why the other answers are wrong
- R-134a — R-134a has no chlorine, so it cannot form phosgene or hydrochloric acid.
- R-600a — Isobutane is a hydrocarbon and burns to carbon dioxide and water.
- R-744 (carbon dioxide) — Carbon dioxide contains no chlorine.
Practice more of this
More EPA 608 Type I practice questions, or see every EPA 608 practice test.
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