【Daily Question】Chemical Engineering Principles 382: Analysis (May 21)
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This post was last edited by “Back to Cambridge” on June 13, 2016, at 17:01. Starting today, the Chemical Engineering Theory section is launching the “Question of the Day” activity, aimed at helping everyone reinforce their basic knowledge in chemical engineering. Subsequently, series such as “Fundamentals of Chemical Engineering”, “Mass Transfer and Separation”, “Chemical Engineering Thermodynamics”, and “Chemical Process Technology” will also be introduced. We hope for your active participation!!! For replies to the “Question of the Day” activity, answers can be viewed directly; however, the thread will be closed after one day! ! To encourage everyone’s continued participation this year! Participation earns 3 wealth points, with an additional 4 wealth points for correct answers~~~ Short answer question: If the precision of the analysis results is high but the accuracy is low, what could be the possible reasons? Reagent and instrument errors
If the precision of the analysis results is high but the accuracy is poor, what might be the cause (instrument error)?
If instrument analysis is used, it is due to the lack of calibration of the instrument； If it is a chemical analysis, it is caused by the standard solution concentration not meeting the requirements.
The instrument is not calibrated, or the standard solution does not meet the requirements
If instrument analysis is used, it is due to the lack of calibration of the instrument; if chemical analysis is used, it is because the concentration of the standard solution does not meet the requirements.
Reagent and instrument errors: If the precision of the analysis results is high but the accuracy is poor, it may be caused by reagent and instrument errors.
If instrument analysis is used, it is due to the lack of calibration of the instrument； In the case of chemical analysis, it is caused by the standard solution concentration not meeting the required levels. What the original poster needs to understand is that precision refers to the degree of variation; high precision means that all the measured values are very close to each other ； Accuracy is the distance between the measured result and the true value, that is, the error; higher accuracy means a smaller error. For an analysis result to be the most accurate data, it must possess both accuracy and precision.