1. Suppose you were not careful in preparing a sample for UV-Vis analysis, so that its actual concentration, c, in methanol was 0.00576 g/L rather than the 0 00600 g/L that you thought it was. a. What is the error, in mg/L, in the mass of the sample present in solution? b. Suppose that a maximum was observed at a wavelength of 278 nm for this solution and that the value of A at this maximum was 0.623 when a 1-cm cell was used. i. Using the value of c that you thought you had for the solution, calcu- late e for the sample, assuming that its molar mass is 100. ii. Show how the information regarding this maximum could be expressed. iii. What is the % error in € associated with the inaccuracy in your know- ing the actual concentration of the solution?

1. Suppose you were not careful in preparing a sample for UV-Vis analysis, so that its actual concentration, c, in methanol was 0.00576 g/L rather than the 0 00600 g/L that you thought it was. a. What is the error, in mg/L, in the mass of the sample present in solution? b. Suppose that a maximum was observed at a wavelength of 278 nm for this solution and that the value of A at this maximum was 0.623 when a 1-cm cell was used. i. Using the value of c that you thought you had for the solution, calcu- late e for the sample, assuming that its molar mass is 100. ii. Show how the information regarding this maximum could be expressed. iii. What is the % error in € associated with the inaccuracy in your know- ing the actual concentration of the solution?

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

Chapter9: Atomic Absorption And Atomic Fluorescence Spectrometry

Section: Chapter Questions

Problem 9.15QAP

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