AbsorbanceBeer-Lambert's Law (Spectrophotometry) #2To spectrophotometrically determine the mass percent of cobalt in an ore containing cobalt and some inertmaterials, solutions with known [Co"] are prepared and the absorbance of each of the solutions ismeasured at the wavelength of optimum absorbance. The data are used to create a calibration plot, shownbelow.0.800.70-8 0.60-0.50-0.40-0.300.20-0.10-++-0.015Concentration (M)A 0.6g sample of the ore is completely dissolved in concentrated HNO3(aq). The mixture is diluted with2+water to a final volume of 50.00 mL. Assume that all the cobalt in the ore sample is converted to Co'(aq).a. What is the (Co] in the solution if the absorbance of a sample of the solution is 0.74?b. Calculate the number of moles of CoT(ag) in the 50.00 mL solution.2+C. Calculate the mass percent of Co in the 0.630 g sample of the ore.

Given data Mass of ore = 0.630 g Volume of solution = 50 ml = 0.05 L Absorbance of solution = 0.74 =…

A 0.630 g sample of the ore is completely dissolved in concentrated HNO3(aq). The mixture is diluted with water to a final volume of 50.00 mL. Assume that all the cobalt in the ore sample is converted to Co (aq). 2+ (aq). a. What is the [Co"] in the solution if the absorbance of a sample of the solution is 0.74? b. Calculate the number of moles of Co"(ag) in the 50.00 mL solution. 2+ C. Calculate the mass percent of Co in the 0.630 g sample of the ore.

A 0.630 g sample of the ore is completely dissolved in concentrated HNO3(aq). The mixture is diluted with water to a final volume of 50.00 mL. Assume that all the cobalt in the ore sample is converted to Co (aq). 2+ (aq). a. What is the [Co"] in the solution if the absorbance of a sample of the solution is 0.74? b. Calculate the number of moles of Co"(ag) in the 50.00 mL solution. 2+ C. Calculate the mass percent of Co in the 0.630 g sample of the ore.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter8: Sampling, Standardization, And Calibration

Section: Chapter Questions

Problem 8.12QAP

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