精華區beta NTUCH-HW 關於我們 聯絡資訊
value in scientific notation without loss of precision. 2. Systematic error: also called determinate error, arises from a flaw in equipment or the design of an experiment. It can be discovered and be corrected. 3. Random error, also called indeterminate error, arises from uncontrolled variables in the measurement. It is always present and cannot be corrected. 4. Precision: reproducibility of a result, in other words, it is how well replicate measurements agree with one another. Usually it can be expressed as a standard deviation. 5. Accuracy: how close a measured value is to the “true value.” 6. Mean: also called the average, is the sum of the measured values divided by n, the number of measurements. 7. Standard deviation: measures how closely the dat are clustered about the mean. 8. Confidence interval: an interval that frequently includes the parameter of interest, if the experiment is repeated. 9. Standard solution: solution which contains known concentrations of analyte. 10.Blank solution: solution which contains all reagents and solvents used in the analysis, but no deliberately add analyte. 11.Method blank: a sample containing all components except analyte, and it is taken through all steps of the analytical procedure. 12.Reagent bland: similar to a method blank, but it has not been subjected to all sample preparation procedures. 13.Field blank: similar to method blank, but it has been exposed to the site of sampling. 14.Standard addition: known quantities of analyte are added to the unknown. From the increase in signal, we deduce how much analyte was in the original unknown. It requires a linear response to analyte. 15.Internal standard: a known amount of a compound, different from analyte, that is added to the unknown. Signal from analyte is compared with signal from the internal standard to find out how much analyte is present.