Please answer all 3 questions 13. The calibration curve for spectrophotometric determination of phosphorus is shown below. Therelationship between the absorbance and the concentration of phosphate in mg/L is given in the figureas well. Calculate the concentration of phosphate if a wastewater sample gives an absorbance of 0.660.1.0A. 12.6 mg/L12.8 mg/LC. 13.0 mg/L13.2 mg/LE. 13.4 mg/Ly = 0.0515x – 0.0221R² = 0.997В.0.8D.0.60.40.20.048.121620Concentration of phosphate (mg/L)A large mine on the island of Cebu in the Philippines was in operation from 1953 until 1994. When themine closed, it left behind waste rock, tailings, open pits, and landfills that are leaching lead toxins into theenvironment. In 2006, mining operations re-commenced, and are also responsible for lead pollution in thearea. One water sample immediate above river sediment was collected and analyzed. Answer Questions 14& 15.14. If the water sample contained 15,231 ppm of lead, what was the molar concentration?А. 3.77 х 106 МВ. 3.77 х 102 МC. 7.35 × 10-² MD. 7.35 × 10-5 MЕ. 1.52 х 104 М15. Determine pE for the water sample. Does this water favor oxidation or reduction?Pb2*(aq) + 2ePb(s)E° = -0.1262 VA. pE = -1.01, oxidization.B. pE = -1.01, reduction.C. pE = -3.14, oxidization.D. pE = -3.14, reduction.E. pE = -0.14, reduction.Absorbance at 470 nm

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13. The calibration curve for spectrophotometric determination of phosphorus is shown below. The relationship between the absorbance and the concentration of phosphate in mg/L is given in the figure as well. Calculate the concentration of phosphate if a wastewater sample gives an absorbance of 0.660. 1.0 A. 12.6 mg/L В. 12.8 mg/L C. 13.0 mg/L D. 13.2 mg/L 13.4 mg/L y = 0.0515x – 0.0221 0.8 R = 0.997 0.6 Е. 0.4 0.2 0.0 4 12 16 20 Concentration of phosphate (mg/L) Absorbance at 470 nm

13. The calibration curve for spectrophotometric determination of phosphorus is shown below. The relationship between the absorbance and the concentration of phosphate in mg/L is given in the figure as well. Calculate the concentration of phosphate if a wastewater sample gives an absorbance of 0.660. 1.0 A. 12.6 mg/L В. 12.8 mg/L C. 13.0 mg/L D. 13.2 mg/L 13.4 mg/L y = 0.0515x – 0.0221 0.8 R = 0.997 0.6 Е. 0.4 0.2 0.0 4 12 16 20 Concentration of phosphate (mg/L) Absorbance at 470 nm

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter27: Molecular Fluorescence Spectroscopy

Section: Chapter Questions

Problem 27.13QAP

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