Mercury(II) forms a 1:1 complex with triphenyl-tetrazolium chloride (TTC) that exhibits an absorption maximum at 255 nm.20 The mercury(II) in a soil sample was extracted into an organic solvent containing an excess of TTC, and the resulting solution was diluted to 100.0 mL in a volumetric flask. Five-milliliter aliquots of the analyze solution were then transferred to six 25-mL volumetric flasks. A standard solution was then prepared that was 5.00 × 10-6 M in Hg(II).Volumes of the standard solution shown in the table were then pipetted into the volumetric flasks, and each solution was then diluted to 25.00 mL. The absorbance of each solution was measured at 255 nm in 1.00-cm quartz cells.

(a) Enter the data into a spreadsheet, and construct a standard-additions plot.

(b) Determine the slope and intercept of the line.

(c) Determine the standard deviation of the slope and of the intercept.

(d) Calculate the concentration of Hg(II) in the analyzed solution.

(e) Find the standard deviation of the measured concentration.

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Volume Standard Solution, mL A225 0.00 0.582 2.00 0.689 4.00 0.767 6.00 0.869 8.00 0.009 10.00 1.127 Volume Standard Solution, mL A225 0.00 0.582 2.00 0.689 4.00 0.767 6.00 0.869 8.00 0.009 10.00 1.127