What is Standard Addition calibration method? Briefly state the application of the standard addition approach in food and pharmaceutical industries. Also briefly explain the methodology to construct a Standard Addition calibration, to estimate the concentration of an unknown sample

Method Note: In steps 1 and 2 you will use the technique of weighing by difference to measure the exact mass of the sample of the ethylenediaminetetraacetic acid copper(II) disodium salt. This technique is described in the 'Techniques' section above and is available to watch as a chemistry skills video online (link available in Moodle). Weigh the ethylenediaminetetraacetic acid copper(II) disodium salt 1. If the sample tube on the balance is not already about one-third filled, fill it to about 1/3 of its height with ethylenediaminetetraacetic acid copper(II) disodium salt. Place a plastic spatula in the sample tube with the ethylenediaminetetraacetic acid copper(II) disodium salt and place on an analytical balance. Tare the balance so that it reads zero. Warning: After carrying out step 1, do not place the spatula on the bench, as this may result in a loss of sample, and hence an incorrect determination of the mass of the sample. 2. Using the spatula, transfer without loss (i.e. don't…

When using a calibration curve and beers law if one of your a diluted test solutions had an absorbance greater than the calibration range. Why is that value disregarded?

Table 1. pH of water samples Sample No. Water Samples pH 1 Tap water from household 6.59 2 Water from creek 7.35 3 Water from river 7.35 4 Unknown sample 7.00 Table 2. Absorbance of Samples Table 3. Calibration Curve Data* Sample No. Absorbance Absorbance 3- Concentration of PO4 Ions, ppm (1 pt each) 1 1.33 1.0 0.050 2 3.26 2.0 0.093 0.89 3.0 0.137 4 0.099 4.0 0.185 5.0 0.230 *Provided by the instructor II. Graph Determination of Phosphate Concentration 3- 1. Using Excel, plot the concentration of PO4* (x-axis) vs. absorbance (refer to Table 3) The olot must show the equation of the best-fit (or trend) line of the graph. Attach the graph below