Roberta decided to find out the content of nickel (Ni) in a sample. She dissolved the 0.0882 g sample in about 30 mL of nitric acid, and after adding an excess of 8- hydroxyquinolinol (HQL), she diluted the solution with deionized water to a final volume of 250 mL. This final solution showed an absorbance of 0.694 at 365 nm, the wavelength of maximal absorbance of the Ni (HQL) complex, when measured in a 1.00 cm cuvette. Knowing that the trendline from the calibration curve for the Ni(HQL) complex at 365 nm is y = 1500x + 0.029 and that the atomic mass of nickel is 58.693 g/mol, calculate the percent content of Ni by mass in the sample. What is the % nickel by mass in the sample? (a) 5.31 percent (b) 7.38 percent. (c) 7.70 percent. (d) 7.4 percent. (e) None of these

Roberta decided to find out the content of nickel (Ni) in a sample. She dissolved the 0.0882 g sample in about 30 mL of nitric acid, and after adding an excess of 8- hydroxyquinolinol (HQL), she diluted the solution with deionized water to a final volume of 250 mL. This final solution showed an absorbance of 0.694 at 365 nm, the wavelength of maximal absorbance of the Ni (HQL) complex, when measured in a 1.00 cm cuvette. Knowing that the trendline from the calibration curve for the Ni(HQL) complex at 365 nm is y = 1500x + 0.029 and that the atomic mass of nickel is 58.693 g/mol, calculate the percent content of Ni by mass in the sample. What is the % nickel by mass in the sample? (a) 5.31 percent (b) 7.38 percent. (c) 7.70 percent. (d) 7.4 percent. (e) None of these

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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