Quiz 2

Question 1

Which of the following best defines “Quality Assurance” in analytical chemistry?
a. The minimum concentration of an analyte that can be accurately quantified.
b. The use of known standards to verify the accuracy of a method.
c. A process to ensure that the results produced are consistent, reliable, and accurate.
d. The concentration at which an analyte can be detected but not necessarily quantified.

Answer 1

c. A process to ensure that the results produced are consistent, reliable, and accurate.

Question 2

“Use objectives” in an analytical procedure primarily refer to:
a. The sensitivity of a method
b. The intended application of the method.
c. The precision of the method.
d. The interference resistance of the method.

Answer 2

b. The intended application of the method.

Question 3

“Sampling requirements” in analytical chemistry dictate:
a. How much analyte to add in spike recovery.
b. The criteria a result must meet.
c. How samples should be collected, stored, and prepared.
d. How a method should be validated.

Answer 3

c. How samples should be collected, stored, and prepared.

Question 4

The concept of “selectivity” in an analytical method is related to:
a. The method’s efficiency at distinguishing the analyte from other substances.
b. The method’s sensitivity to low concentrations of analyte.
c. The criteria set for the method’s results.
d. The method’s suitability for its intended use.

Answer 4

a. The method’s efficiency at distinguishing the analyte from other substances.

Question 5

In analytical chemistry, “sensitivity” refers to:
a. The ability to separate the analyte from other substances.
b. The response of the method to a change in the amount of analyte.
c. The concentration of analyte added during a spike recovery.
d. The criteria set for the method’s results.

Answer 5

b. The response of the method to a change in the amount of analyte.

Question 6

“Calibration checks” are essential to:
a. Introduce a known amount of analyte into a sample.
b. Ensure that an instrument or method is producing results within a known and acceptable range.
c. Establish the limit at which an analyte can be detected.
d. Set the criteria for method results.

Answer 6

b. Ensure that an instrument or method is producing results within a known and acceptable range.

Question 7

“Quality control samples” are used to:
a. Define the limit of detection for a method.
b. Determine the concertation of an analyte in a sample.
c. Monitor the ongoing performance and consistency of an analytical process.
d. Check the selectivity of an analytical method.

Answer 7

c. Monitor the ongoing performance and consistency of an analytical process.

Question 8

The primary goal of “assessment” in analytical chemistry is to:
a. Introduce a known amount of analyte into a sample.
b. Evaluate the performance and reliability of an analytical method.
c. Establish the limit at which an analyte can be detected.
d. Provide detailed criteria for method results.

Answer 8

b. Evaluate the performance and reliability of an analytical method.

Question 9

The “standard addition” method is used to:
a. Define the limit of detection for a method.
b. Determine the concentration of an analyte in a sample by adding known amounts of that analyte and measuring the response.
c. Assess the validity of an analytical method.
d. Check for contamination in the reagents used.

Answer 9

b. Determine the concentration of an analyte in a sample by adding known amounts of that analyte and measuring the response.

Question 10

The “limit of quantitation” (LOQ) is:
a. The minimum concentration of an analyte that can be reliably detected.
b. The concentration of analyte added during a spike recovery.
c. The concentration at which an analyte can be detected but not necessarily quantified.
d. The minimum concentration of an analyte that can be quantified with acceptable accuracy and precision.

Answer 10

d. The minimum concentration of an analyte that can be quantified with acceptable accuracy and precision.