The following are results from Part A of Lab 3. Identify the unknown metal cationTable 1: Observations for Qualitative Spot Tests Between Solutions Containing Single MetalCation and Various Test Reagents from Part ATest ReagentK,Cr04KSCNNH3DMGHCIH2SO4ppt,yellow, appt,white,ppt,white, appt, white,Pb2NRNRsomelotlotsomeppt,CC, lightC,yellowCC,CC, darkppt, brown, aFeorange,redlotbrowncolourlesssomeCC, lightblue/violetppt, pink, alotNiNRNRNRNRppt,brown, appt,white, appt,Ag*white, aNRNRNRlotlotlotppt,white, appt,ppt, white,Ba+yellow, aNRNRNRsomelotlotK2Cr04KSCNNH3DMGHCIH2SO4ppt,ppt, white,a lotppt,white, aUnknownbrown, aNRNRNRlotlotSelect one:O Ag*O Pb2+O Ni?+O Fe?+O Ba2+O None of the AboveMetal Cation Tested

Answered: Image /qna-images/answer/2a37872f-4910-4b1f-8970-c5581c199261.jpg

The following are results from Part A of Lab 3. Identify the unknown metal cation Table 1: Observations for Qualitative Spot Tests Between Solutions Containing Single Metal Cation and Various Test Reagents from Part A Test Reagent K,Cr04 KSCN NH3 DMG HCI H2SO4 ppt, yellow, a ppt, white, ppt, white, a ppt, white, Pb2 NR NR some some lot lot ppt, CC, light CC, yellow CC, CC, dark ppt, brown, a Fe orange, colourless red lot brown some CC, light blue/violet ppt, pink, a lot Ni2+ NR NR NR NR ppt, white, a ppt, ppt, Ag* brown, a white, a NR NR NR lot lot lot ppt, yellow, a lot ppt, white, a ppt, white, Ba NR NR NR some lot K2Cr04 KSCN NH3 DMG HCI H2SO4 ppt, ppt, ppt, white, a lot Unknown brown, a NR NR white, a NR lot lot Select one: O Ag* O Pb2+ O Ni?+ O Fe3+ O Ba2+ O None of the Above Metal Cation Tested

The following are results from Part A of Lab 3. Identify the unknown metal cation Table 1: Observations for Qualitative Spot Tests Between Solutions Containing Single Metal Cation and Various Test Reagents from Part A Test Reagent K,Cr04 KSCN NH3 DMG HCI H2SO4 ppt, yellow, a ppt, white, ppt, white, a ppt, white, Pb2 NR NR some some lot lot ppt, CC, light CC, yellow CC, CC, dark ppt, brown, a Fe orange, colourless red lot brown some CC, light blue/violet ppt, pink, a lot Ni2+ NR NR NR NR ppt, white, a ppt, ppt, Ag* brown, a white, a NR NR NR lot lot lot ppt, yellow, a lot ppt, white, a ppt, white, Ba NR NR NR some lot K2Cr04 KSCN NH3 DMG HCI H2SO4 ppt, ppt, ppt, white, a lot Unknown brown, a NR NR white, a NR lot lot Select one: O Ag* O Pb2+ O Ni?+ O Fe3+ O Ba2+ O None of the Above Metal Cation Tested

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

Chapter14: Applications Of Ultraviolet-visible Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 14.18QAP

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You wish to measure the iron content of the well water on the new property you are about to buy. You prepare a reference standard Fe3+ solution with a concentration of 5.74×10−4 M. You treat 14.0 mL of this reference with HNO3 and excess KSCN to form a red complex and dilute the reference to 60.0 mL. The diluted reference is placed in a cell with a 1.00‑cm light path. You then take 30.0 mL of the well water, treat with HNO3 and excess KSCN, and dilute to 100.0 mL. This diluted sample is placed in a variable pathlength cell. The absorbance of the reference and the sample solutions match when the pathlength is 1.76 cm. What is the concentration of iron in the well water? For each solution, the zero is set with a blank.
You wish to measure the iron content of the well water on the new property you are about to buy. You prepare a reference standard Fe3+ solution with a concentration of 5.53×10−4 M. You treat 10.0 mL of this reference with HNO3 and excess KSCN to form a red complex and dilute the reference to 45.0 mL. The diluted reference is placed in a cell with a 1.00‑cm light path. You then take 20.0 mL of the well water, treat with HNO3 and excess KSCN, and dilute to 100.0 mL. This diluted sample is placed in a variable pathlength cell. The absorbance of the reference and the sample solutions match when the pathlength is 3.25cm. What is the concentration of iron in the well water? For each solution, the zero is set with a blank.
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