Question 1009 of 229 · California Water Distribution Operator Exam
A chlorine dose of 3.0 mg/L produces a free chlorine residual of 0.8 mg/L after the contact time. What is the chlorine demand?
Exactly one answer is correct.
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Correct answer to question 1009
- B: 2.2 mg/L
Explanation
Demand = dose minus residual, so 3.0 - 0.8 = 2.2 mg/L. Adding the two (3.8) is a common mistake.
More questions: Disinfection
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