Question 1019 of 229 · California Water Distribution Operator Exam
At which pH is free chlorine the most effective disinfectant?
Exactly one answer is correct.
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Correct answer to question 1019
- B: Lower pH, where more hypochlorous acid is present
Explanation
Free chlorine splits into HOCl and OCl-, and HOCl is far stronger. As pH rises, more OCl- forms and the disinfection power falls.
More questions: Disinfection
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