What mass of the CuCl₂·2H₂O (170.48 g/mol) should be weighed in order to prepare the 250.0 mL Cu(II) (63.546 g/mol) stock solution?What is the mass of Cu in the unknown sample solution?What is the most probable identity of the unknown copper compound, assuming there is 1 mole of Cu per mole of the unknown? A UV-Vis spectrophotometry experiment for the determination of an unknown copper compounds wascarried out by first preparing 250.0 mL of a 100.0 mg/L Cu(II) stock solution using a 100% purecopper(II) chloride dihydrate, CuCl, 2H20. Appropriate volumes of this stock solution were thenpipetted, added with concentrated ammonia, and diluted in volumetric flasks to come up with 50.00-mLstandard solutions with concentrations of 0, 2.50, 5.00, 10.00, 25.00, and 50.00 mg/L. For the coppersample, a 50.00-mL solution was prepared by dissolving 3.25 mg of the unknown compound. Theabsorbance of the blank, standards, and the unknown sample were then measured at the analyticalwavelength of 610 nm. The relevant data are shown below.ITIISolutionConcentration (mg/L)Volume (mL)AbsorbanceBlank50.000.028Standard 12.5050.000.121Standard 25.0050.000.222Standard 3Standard 410.0050.000.44225.0050.000.902Standard 550.0050.001.920Sample50.000.989

Given that, Molar mass of CuCl2.2H2O = 170.48 g/mol Molar mass of copper = 63.55 g/mol

What mass of the CuCl₂·2H₂O (170.48 g/mol) should be weighed in order to prepare the 250.0 mL Cu(II) (63.546 g/mol) stock solution? What is the mass of Cu in the unknown sample solution? What is the most probable identity of the unknown copper compound, assuming there is 1 mole of Cu per mole of the unknown?

What mass of the CuCl₂·2H₂O (170.48 g/mol) should be weighed in order to prepare the 250.0 mL Cu(II) (63.546 g/mol) stock solution? What is the mass of Cu in the unknown sample solution? What is the most probable identity of the unknown copper compound, assuming there is 1 mole of Cu per mole of the unknown?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter27: Molecular Fluorescence Spectroscopy

Section: Chapter Questions

Problem 27.9QAP

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