1- A calibration plot to model Beer’s Law is constructed for a range of [FeSCN]^{2+} solutions between 1.00 x 10^{-5} M and 5 x 10^{-4} M. The equation of the line is y=5325x. Determine the molar absorptivity of FeSCN^{2+} in this range.
2- An unknown FeSCN^{2+} solution is prepared by adding 8.00 mL of 2.00 x 10^{-3} M Fe(NO_{3})_{3}, 4.00 mL of 2.00 x 10^{-3} M KSCN, and 3.00 mL of water. The absorbance of the unknown [FeSCN]^{2+} solution is 0.482. Calculate the equilibrium concentration of [FeSCN]^{2+} (using the calibration plot in Question 1).
3- An unknown [FeSCN]^{2+} solution is prepared by adding 8.00 mL of 2.00 x 10^{-3} M Fe(NO_{3})_{3}, 4.00 mL of 2.00 x 10^{-3} M KSCN, and 3.00 mL of water. The absorbance of the unknown [FeSCN]^{2+} solution is 0.482. Calculate the equilibrium constant for the formation of [FeSCN]^{2+}.
4- An unknown FeSCN^{2+} solution is prepared by adding 8.00 mL of 2.00 x 10^{-3} M Fe(NO_{3})_{3}, 4.00 mL of 2.00 x 10^{-3} M KSCN, and 3.00 mL of water. Calculate the initial concentration of Fe(NO_{3})_{3} added.
5- An unknown FeSCN^{2+} solution is prepared by adding 8.00 mL of 2.00 x 10^{-3} M Fe(NO_{3})_{3}, 4.00 mL of 2.00 x 10^{-3} M KSCN, and 3.00 mL of water. Calculate the initial concentration of KSCN added.
1- A calibration plot to model Beer’s Law is constructed for a range of [FeSCN]2+ solutions...
After completing Part A of this experiment, a student determines the slope of their calibration graph of absorbance versus [FeSCN2] to be 5140 M1. In Part B, a student combines 2.00 mL of a 0.00200 M solution of KSCN with 5.00 mL of 0.00200 M solution of Fe(NO,), and 3.00 mL of water. The following equilibrium is established. Fe (aq) + SCN (aq) FeSCN (aq) The absorbance of the equilibrium solution is measured as 0.246. What is the equilibrium constant...
4 please in part 1 gires us absorbance values for each sample , changes in concentration and absorbance will cause a curve 1. For each new concentration of FeSCN2+ a new absorbance will be plotted. 4. After completing Part A of this experiment, a student determines the slope of their calibration graph of absorbance versus (FeSCN to be 5140 M". In Part B, a student combines 2.00 mL of a 0.00200 M solution of KSCN with 5.00 mL of a...
What's the concentration of [FeSCN2+] using limiting reactant theory and equation? For each test tube solution enter the initial concentration of Fe+ and SCNthe equilibrium concentration of FeSCN2: into the ICE table given. Complete entries for the rest of the table and calculate the K value for each of the tables. The values of K should be confined to a narrow range to reflect constancy. Comment on the quality of your work in this regard and calculate the average K....
0.0018 is a wrong answer. Please do it again. Question 6 of 10 Try Again > Attempt 3 A standard solution of FeSCN2+ is prepared by combining 9.0 mL of 0.20 M Fe(NO3), with 1.0 mL of 0.0020 M KSCN. The equation for the reaction is as follows. Fe(NO3)3 + KSCN=FeSCN2+ + KNO, +2 NO; What allows us to assume that the reaction goes essentially to completion? The concentration of Fe(NO,), is much higher than the concentration of KSCN. The...
fill out the chart Lab Notebook Initial concentrations of Feº and SCN KSCN, mL Di water, mL (Fe) Solution Fe(NO3). mL M [SCN] initia M Spectrophotometric determination of (FeSCN) (Calibration curve: A =1269.6c) Solution Measured absorbance Calculated (FeSCN).M alvo Instructions In separate test tubes, make the 5 solutions according to the table below. Then stir each solution. Solution Fe(NO3)3, mL KSCN, mL 2.00 x 10M 2.00 x 10M Dl water, ml 5.0 5.0 0.0 5.0 4.0 1.0 5.0 3.0 2.0...
Fe3(aq) FESCN (aq) SCN (aq) In this experiment, we'll be examining the temperature-dependence of the rate constant for the reaction above. 1. Using the UV-Vis instrument, you measured a room temperature absorbance for FESCN2 at 477 nm of 0.815. What is its concentration in molarity (M)? Please show all work. The molar absorptivity for FeSCN2 is 4,258 м"сm1 a. Answer: b. You calculated the [FeSCN2] above from the observed room temperature absorbance. Which one of the following statements about the...
Lab Report: Determination of Kc for a Complex Ion Formation tube 2.00e-3 Fe3+ (mL) 2.00E-3M SCN- (mL) water (mL) initial conc. Fe3+ initial conc. SCN- 1 5.00 5.00 0 1.00e-3M 1.00E-3M 2 5.00 4.00 1.00 1.00E-3M 8.00E-3M 3 5.00 3.00 2.00 1.00E-3, 6.00E-3M 4 5.00 2.00 3.00 1.00E-3M 4.00E-3M 5 5.00 1.00 4.00 1.00E-3M 2.00E-3M 10ml of 0.200M Fe3+, 2.00ml of 0.00200M SCN-, AND 8.00ml of water results in an eq. [FeSCN2+] IN Standard Soln.:2.00E-4M Could you please explain how...
Resume < Question 6 of 10 > Attempt 1 - A standard solution of FeSCN is prepared by combining 9.0 ml of 0.20 M Fe(NO), with 1.0 mL of 0.0020 M KSCN. The equation for the reaction is as follows. Fe(NO3), + KSCN = FeSCN2+ + KNO, +2 NO; What allows us to assume that the reaction goes essentially to completion? The concentration of Fe(NO,), is much higher than the concentration of KSCN. The excess Fe" prevents the formation of...
A student made solution #3 using the experimental method in this lab, and measured an absorbance of 0.559. The starting reagents are 2.00 x 10-3 M Fe(NO3)3 and 2.00 x 10-3 M KSCN. The amount of absorption is proportional to the concentration of FeSCN2+. This relationship – true for many solutions – is called “Beer’s Law”, and has the simple equation: A = bc where “A” is the absorption, “b” is 5174.6 for FeSCN2+ and “c” is molarity Make Five...
Table A. Preparation of Standard solutions of FeSCN2+ 1.0 M HNO3 0.002 M 0.200 M Solution KSCN (mL) Fe(NO3)3 (mL) 0.5 5 [FeSCN2+] (mol/L)* 1 4.0x10^-5 Add 1.0 M 2 1.0 5 8.0x10^-5 HNO3 3 1.5 5 1.2x10^-10 4 2.0 5 1.6x10-4 to each to adjust the volume to 25 mL. 5 2.5 5 2.0x10-4 * Calculate the concentrations of FeSCN2+ in each beaker, assuming that all SCN-ions exist as FeSCN2+. In other words, [FeSCN2+] (in Soln 1) = [SCN-]...