18-16. A compound with a molecular mass of 292.16 was dissolved in a 5-mL volumetric flask. A 1.00-mL aliquot was withdrawn, placed in a 10-mL volumetric flask, and diluted to the mark. The absorbance at 340 nm was 0.427 in a 1.000-cm cuvet. The molar absorptivity for this compound at 340 nm is ɛ340 = 6 130 M-1 cm-!. (a) Calculate the concentration of compound in the cuvet. (b) What was the concentration of compound in the 5-mL flask? (c) How many milligrams of compound were used to make the 5-mL solution?

18-16. A compound with a molecular mass of 292.16 was dissolved in a 5-mL volumetric flask. A 1.00-mL aliquot was withdrawn, placed in a 10-mL volumetric flask, and diluted to the mark. The absorbance at 340 nm was 0.427 in a 1.000-cm cuvet. The molar absorptivity for this compound at 340 nm is ɛ340 = 6 130 M-1 cm-!. (a) Calculate the concentration of compound in the cuvet. (b) What was the concentration of compound in the 5-mL flask? (c) How many milligrams of compound were used to make the 5-mL 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

Chapter13: An Introduction To Ultraviolet-visible Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 13.24QAP

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