Spectrophotometric Determination of a Metal A 100.00 mL of exactly 250.0 mg/L Cu2+ stock solution was prepared using a 99.95% pure Ču(NO3)2·3H2O (241.60 g/mol). From this stock, a series of standard solutions were prepared by pipetting certain volumes into 100-mL volumetric flasks, followed by adding 2.00 mL of concentrated NH3, and finally diluting to mark with deionized water. Additionally, a blank solution was prepared by using only NH3 and distilled water. Question: Why was NH3 added to each standard solution before diluting with distilled water? What will be the resulting color of the solution and why is this the color that is observed?

Spectrophotometric Determination of a Metal A 100.00 mL of exactly 250.0 mg/L Cu2+ stock solution was prepared using a 99.95% pure Ču(NO3)2·3H2O (241.60 g/mol). From this stock, a series of standard solutions were prepared by pipetting certain volumes into 100-mL volumetric flasks, followed by adding 2.00 mL of concentrated NH3, and finally diluting to mark with deionized water. Additionally, a blank solution was prepared by using only NH3 and distilled water. Question: Why was NH3 added to each standard solution before diluting with distilled water? What will be the resulting color of the solution and why is this the color that is observed?

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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