Here is a use objective for a chemical analysis to be performed at a drinking water purification plant: "Data and results collected quarterly shall will be used to determine whether the concentrations of haloacetates in the treated water demonstrate compliance with the levels set by the Stage 1 Disinfection By-products Rule using Method 552.2"(a specification that sets precision, accuracy, and other requirements).

Which one of the following questions best summarizes the meaning of the use objective?

(i) Are haloacetate concentrations known within specified precision and accuracy?

(ii) Are thehaloacetates detectable in the water?

(iii) Dothehaloacetate concentrations exceed the regulatory limit?

Short Answer

Expert verified

Amongst statements i, ii, and iii, statement iii is the right answer.

Step by step solution

01

Definition of chemical analysis

Chemical analysis is the study of a substance's chemical composition and structure. More broadly, it can be thought of as the collection of all procedures for obtaining precise chemical data.

02

Reason for right answer

Statement 3 is the right answer.

The purpose of the analysis is to check if concentrations do not go beyond the levels set by a definite rule.

03

Reason for wrong answer

Statements 1 and 2 are wrong because the queries about precision, and accuracy, and detectability in water are irrelevant to the data collection


Conclusion

The question above explained how the data and results collected quarterly will be used to determine whether the concentrations of haloacetates in the treated water are in compliance with the statutory levels..

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