Following the experimental procedure described in the lab manual, a student combined 5.00 mL of 0.0020 M Fe³+ and 1.00 mL of 0.0020 M SCN¯ with 4.00 mL of water to create their Trial 1 solution. The student used their spectrophotometer to measure the absorbance of the reaction mixture and recorded an absorbance of 0.095. Given these experimental conditions and results, please calculate the following (be sure to save you work in case you need help from your instructor): a. The initial concentration of Fe3+: M (give to nearest 0.0001 M) b. The initial concentration of SCN': M (give to nearest 0.0001 M) c. The equilibrium concentration of FeSCN2+: (give as decimal to nearest 0.000 001) Hint: The extinction coefficient of FeSCN2+ is 4,630 M-1°cm-1 and the cuvettes we use have a path length of 1.0 cm. d. The equilibrium concentration of Fe3+: M (give as decimal to nearest 0.000 001 M) e. The equilibrium concentration of SCN': M (give as decimal to nearest 0.000 001 M) f. The equilibrium constant K: (give to nearest tens place)

Following the experimental procedure described in the lab manual, a student combined 5.00 mL of 0.0020 M Fe³+ and 1.00 mL of 0.0020 M SCN¯ with 4.00 mL of water to create their Trial 1 solution. The student used their spectrophotometer to measure the absorbance of the reaction mixture and recorded an absorbance of 0.095. Given these experimental conditions and results, please calculate the following (be sure to save you work in case you need help from your instructor): a. The initial concentration of Fe3+: M (give to nearest 0.0001 M) b. The initial concentration of SCN': M (give to nearest 0.0001 M) c. The equilibrium concentration of FeSCN2+: (give as decimal to nearest 0.000 001) Hint: The extinction coefficient of FeSCN2+ is 4,630 M-1°cm-1 and the cuvettes we use have a path length of 1.0 cm. d. The equilibrium concentration of Fe3+: M (give as decimal to nearest 0.000 001 M) e. The equilibrium concentration of SCN': M (give as decimal to nearest 0.000 001 M) f. The equilibrium constant K: (give to nearest tens place)

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter1: Introduction

Section: Chapter Questions

Problem 1.11QAP

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