Table 1: Absorbance data recorded for five 0.200 M Fe(NO:)3 solutions at 20.0 °CBeaker0.0020 M[FESCN2+] (M) Abs.0.00200SCN (mL)Fe(NO3)3(mL)5.00.000.00 M-0.00125.02.008.0 x 10-5 M0.2785.03.001.2 x 10-4 M0.41545.04.001.6 x 10-4 M0.5555.05.002.0 x 10-4 M0.671Part 1: y=3386x+0.0043R^2=0.9991Part II – Determining Concentration of an UnknownTable 2: Best-fit line and Absorbance data of unknown solutionBest-fit line equation from Part IAbsorbance reading of unknown0.338Part III – Determining the Equilibrium ConstantTest tube0.0020 M0.00200H20 (mL)Abs.Net AbsFe(NO3)3(mL)SCN-(mL)13.000.007.000.00023.002.005.000.1190.11933.003.004.000.2120.21243.004.003.000.2650.26553.005.002.000.3350.335 Postab questions:Part I- Creating a Calibration Line1. Compare the color of the solutions in each of the five test tubes in Part I. Recall from theintroduction, that the product FESCN*² has a deep red color. In 1-2 sentences, explainwhat you think the color changes indicate for the equilibrium of these reaction solutions.Part II - Determining the Concentration of an Unknown2. Use the trendline equation from the calibration plot (that you wrote down in Table 2) tocalculate the concentration of the unknown solution. Hìnt: the trendline equation is inthe format of y = mx + b, where y is the absorbance (from Table 2) and x is the unknownconcentration (that you will solve for). Try to show your work by typing into the groupdiscussion, or you have the option to hand-write and submit a picture of your hand-written work.Part III – Determining the Equilibrium Constant3. Refer to the absorbance data you wrote down in Table 3. Use the same trendline equationfrom the calibration plot (from Part II, Table 2) to calculate the concentration of thesolution from test tube #2. Hint: follow the same procedure as postlab Q2, but use thenet absorbance of test tube#2 to plug in for y. Show your work (either typed or hand-written)4. Calculate the initial concentration of Fe3+ in test tube #2. Hint: use M¡V1=M;V2, whereV2 is a total of 10.0 mLa Show your work.5. Calculate the initial concentration of SCN in test tube #2, where again V2 is 10.0 mL.6. Write and fill out the following ICE table, using concentrations for test tube #2. Hint:the initial concentrations of Fe* and SCN were calculated in Q4 and Q5, and theequilibrium concentration of FeSCN*? was calculated in Q3.[Fe*L[SCN-'L[FESCN-LInitialChangeEquilibrium

Solution: In colorimetry experiment we plot absorbance vs Concentration. we get a straight which…

2. Use the trendline equation from the calibration plot (that you wrote down in Table 2) to calculate the concentration of the unknown solution. Hint: the trendline equation is in the format of y = mx + b, where y is the absorbance (from Table 2) and x is the unknown concentration (that you will solve for). Try to show your work by typing into the group discussion, or you have the option to hand-write and submit a picture of your hand- written work.

2. Use the trendline equation from the calibration plot (that you wrote down in Table 2) to calculate the concentration of the unknown solution. Hint: the trendline equation is in the format of y = mx + b, where y is the absorbance (from Table 2) and x is the unknown concentration (that you will solve for). Try to show your work by typing into the group discussion, or you have the option to hand-write and submit a picture of your hand- written work.

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 14.12QAP

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For Indirect Iodometric Analysis of Copper... ~0.0896g KIO3 necessary to consume 350mL of 0.1 M Na2S2O3, Na2S2O3 is stored in an amber glass bottle until ready for use. Primary Standard KIO3 has 2g of KI, 50mL of DI water, and 10 mL of 1.0M HCl is added then immediately titrated with Na2S2O3 until medium yellow or straw... then 5mL of starch indicator is added and titrated again until blue black color turns clear. Unknown CuO use 1.2G of Unknown, 20mL of HNO3 heated until sample dissolved, 25 mL of DI water added and boiled until clear light blue color, after cooling 1:1 NH3 added (~34.47 mL of NH4OH reagent) until permanent deep blue color amine complex, 2g of NH4HF2 added and swirled until dissolved, 3 g of KI is added then titrated immediately with Na2S2O3 until brown color of iodide is nearly gone (brown milk color), 2 g of KSCN and 3 mL of starch indicator is then added with titration continuing until disappearance of new blue black color. 4. Why is the starch indicator solution…