Measuring colorimeter precision and accuracy
Jo Long — Tue, 2012-05-15 16:40
To calculate the accuracy of the colorimeter we have used the ammonia colorimetric assay. A freshly opened 12.2 ppm ammonia standard solution (Ricca Chemical Company from Scientific Stategies Cat # 5450-4RC) was carefully diluted with distilled water as follows:
Each dilution was carried out in duplicate and the API ammonia test kit was used to develop 1 mL of each solution in triplicate. Absorbance was measured with the colorimeter red LED and data is shown in the Table below.
|Ammonia (ppm)||Absorbance #1||Absorbance #2||Absorbance #3||Absorbance Mean||SD||*Colorimeter Reading||Accuracy (ppm)|