Question 4020 of 223 · California Water Treatment Operator Exam
Which action reduces the risk of cross-contamination when dealing with reagents in a lab?
Exactly one answer is correct.
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Correct answer to question 4020
- B: Using clean glassware and not returning unused reagent to the bottle
Explanation
Returning chemical to the stock bottle can contaminate it. Labeled, clean containers and dedicated tools protect the quality of results.
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