Atomic Absorption Spectroscopy (AAS) Quantitation

You are determining the lead (Pb) content in a soil sample using flame AAS. The calibration standards give the following data: 0 ppm → A=0.000, 2 ppm → A=0.098, 5 ppm → A=0.245, 10 ppm → A=0.492, 20 ppm → A=0.975. The soil extract gives A=0.368. (a) Determine the equation of the calibration curve and the Pb concentration in the soil extract. (b) Calculate the sensitivity (characteristic concentration). (c) What are the advantages of graphite furnace AAS over flame AAS? (d) How would you correct for matrix effects?