Question 1002 of 234 · California Wastewater Operator Exam
Which gas is heavier than air and tends to collect in manholes and wet wells?
Exactly one answer is correct.
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Correct answer to question 1002
- B: Hydrogen sulfide
Explanation
Hydrogen sulfide is about 20 percent heavier than air and settles in low spaces. Methane, ammonia and hydrogen are lighter than air and rise.
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