How can you validate precision and accuracy?

Short Answer

Expert verified

Precision is validated by the repeatability of analyses of replicate samples and replicate portions of the same sample and accuracy is validated by analyzing certified reference materials, by relating results from different analytical methods.

Step by step solution

01

Precision and Accuracy

Precision is validated by the repeatability of analyses of replicate samples and replicate portions of the same sample.

Accuracy:

Accuracy is validated by analyzing certified reference materials, by relating results from different analytical methods,

They are,

Fortification (spike) recovery,

Standard additions,

Calibration checks,

02

Ways to illustrate accuracy

There are several ways to illustrate accuracy. Such actions include:

1. Performing calibration checks in order to assure that the instruments are properly calibrated and therefore would work properly;

2. Testing for fortification/spike recoveries - in this process, we can see if the response from a calibration curve matches the response to the spike;

3. Introducing quality control samples for the elimination of any bias introduced; and

4. Introducing blanks to account for the interference of other species in the sample. To demonstrate precision, we can replicate both our samples, and portions of the same sample.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A solution containing3.47mMX(analyte) and1.72mMS(standard) gave peak areas of3473and 10222,respectively, in a chromatographic analysis. Then1.00mLof 8.47mMSwas added to5.00mLof unknownX,and the mixture was diluted to10.00mL. This solution gave peak areas of5428and4431forXandS, respectively.

(a) Calculate the response factor for the analyte.

(b) Find the concentration of S(mM)inthe10.0-mLmixture.

(c) Find the concentration of X(mM)inthe10.0-mLmixture.

(d) Find the concentration ofXintheorignalunknown.

Control chart. A laboratory monitoring perchlorate (CIO-4)in urine measured quality control samples made from synthetic urine spiked withCIO-4. The graph in Box5-2shows consecutive quality control measurements. Are any troubleshooting conditions from Box 5-2 observed in these data?

5-28. Ititandard addition. Lead in dry river sediment was extracted with 25wt%HNO3at35°Cfor1h.then1.00mLof filtered extract was mixed with other reagents to bring the total volume to V0=4.60mL.pb(ll)was measured electrochemically with a series of standard additions of 2.50pb(ll).


(a) Volume is not constant, so follow the procedure of Figures 5-5 and 5-6 to find ppmpb(ll)inthe1.00-mL

extract.

(b) Find the standard uncertainty and 95%confidence interval for the x-intercept of the graph. Assuming that uncertainty in intercept is larger than other uncertainties, estimate the uncertainty in ppm pb(ll)inthe1.00-mLextract.

Distinguish raw data, treated data, and results.

State when standard additions and internal standards, instead of a calibration curve, are desirable, and why.

See all solutions

Recommended explanations on Chemistry Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free