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?

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

Chapter15: Molecular Luminescence Spectrometry

Section: Chapter Questions

Problem 15.10QAP

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