Which are TRUE statements regarding internal standards?
I The response factor is calculated by using a mixture containing known amounts of analyte and internal standard and by using detector response to the analyte and the internal standard.
II Internal standards are useful where instrument response or quantity of sample analyzed varies over time.
III Detector response is inversely proportional to concentration.
IV Detector response to analyte and internal standard is assumed to be constant over a range of concentrations.
A)I,II,and III
B)II,III,and IV
C)I and II
D)I and III
E)I,II,and IV

Question

Quizplus · Accepted Answer

All four statements are related to internal standards and their calculation, usefulness and detector response. Statement I explains how response factor is calculated, which is the ratio of the detector response to the analyte and internal standard. Statement II highlights the usefulness of internal standards where instrumental response or quantity of sample analyzed varies over time. Statement III is true with regards to detector response, which is inversely proportional to the concentration. Statement IV is also true, as the detector response should be assumed to be constant over a range of concentrations in order to avoid inaccuracies in the calculation. Therefore, the correct choice is E, which includes all the true statements about internal standards.

Which Are TRUE Statements Regarding Internal Standards