The molar absorptivity for cobalt and nickel complexes with 2,3-quinoxalinedithiol are 3.64x104L/M-cm for Co at 510nm, 5.52x103L/M-cm and 1.24x103L/M-cm for Co at 656nm and 1.75x104L/M-cm for Ni. A 250mg soil sample that was collected near an industrial metal-processing plant is dissolved, and masking agent is added to avoid interference from other metals present. Color is developed by adding the complexing agent and the sample is diluted to 100.00ml. The absorbance at 510nm is 0.517 and at 656nm it is 0.405 in a 1.00cm cell. Calculate the weight percent of Co and Ni in the soil.

The molar absorptivity for cobalt and nickel complexes with 2,3-quinoxalinedithiol are 3.64x104L/M-cm for Co at 510nm, 5.52x103L/M-cm and 1.24x103L/M-cm for Co at 656nm and 1.75x104L/M-cm for Ni. A 250mg soil sample that was collected near an industrial metal-processing plant is dissolved, and masking agent is added to avoid interference from other metals present. Color is developed by adding the complexing agent and the sample is diluted to 100.00ml. The absorbance at 510nm is 0.517 and at 656nm it is 0.405 in a 1.00cm cell. Calculate the weight percent of Co and Ni in the soil.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter26: Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 26.5QAP

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