Gold can be determined in solutions containing high concentrations of diverse ions by fCP-AES.29 Aliquots of 50.0 mL of the sample solution were transferred to each of four 100.0 mL volumetric flasks. A solution was prepared containing 10.0 mg/L Au in 20% H2SO4 and quantities of this solution were added to the sample solutions to give 0, 2.5, 5, and 10 mg/L added Au in each of the flasks. The solutions were made up to a total volume of 100.0 mL, mixed, and analyzed by ICP-AES. The resulting data are presented in the following table.
(it) Use a spreadsheet to perform a least-squares analysis to determine the slope, intercept, and regression statistics, including the standard deviation about regression.
(b) Use your results to find the concentration of gold in the sample solution in mg/L.
(c) The known concentration of gold in the sample is 8.51 mg/L. Test the hypothesis that your result is equal to this value at the 95% confidence level.
(d) Compare your result to the result reported by Whitehead et aI., and comment on any differences.