A) From the table you completed in Pre-lab question #1 from Exp. 25 in your lab manual, what is the initial SCN- concentration for solution 1?

B) From the table you completed in Pre-lab question #1 from Exp. 25 in your lab manual, what is the initial SCN- concentration for solution 4?

C) From the table you completed in Pre-lab question #1 from Exp. 25 in your lab manual, what is the equilibrium Fe(SCN)2+ concentration for solution 5?

D) Imagine that you plotted the absorbance and Fe(SCN)2+ concentration data from the table you’ve completed in Pre-lab Question #1 of Exp. 25 in your lab manual. By plotting this absorbance versus concentration data you would have a standard curve. Then, you take an absorption spectrum of a solution which has an unknown Fe(SCN)2+equilibrium concentration. The absorbance of the solution is determined to be 0.840. Which of the following equilibrium concentrations of Fe(SCN)2+ most closelycorresponds to the solution for which the absorbance was measured?

E)An equilibrium solution is prepared by mixing 2.750 mL of 0.001650 M SCN-, 5.000 mL of 0.001650 M Fe3+, and 2.750 mL of 0.05000 M HNO3. The equilibrium solution’s absorbance is determined to be 0.9150. Using this absorbance value and a standard curve, you determine that the equilibrium concentration of Fe(SCN)2+ is 0.0001830 M. Prepare an ICE table for the equilibrium mixture. Include the initial concentrations, changes in concentrations, and the equilibrium concentrations of Fe3+, SCN- and Fe(SCN)2+. Using the information in your ICE table, calculate the equilibrium constant. What is the value of the equilibrium constant?

 

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1. Complete the table below by calculating the initial SCN and equilibrium Fe(SCN)2+ concentrations for each of the five standard solutions. In addition to the volume of KSCN indicated in the table below, each solution contains 5.00 mL of Fe(NO3)3 and sufficient 0.050 M HNO3 to produce a total volume of 25.00 mL of solution. Solution 1 2 3 4 10 5 Molarity of KSCN 0.00165 M Vol. SCN 5.00 mL 4.00 mL 3.00 mL 2.00 mL Fe³+ +SCN=Fe(SCN)²+ 1.00 mL Molarity of Fe(NO3)3 0.165 M Initial SCN M Fe(SCN)²+ M Absorbance 1.590 1.320 0.990 0.690 0.335 1. Complete the table below by calculating the initial SCN and equilibrium Fe(SCN)2+ concentrations for each of the five standard solutions. In addition to the volume of KSCN indicated in the table below, each solution contains 5.00 mL of Fe(NO3)3 and sufficient 0.050 M HNO3 to produce a total volume of 25.00 mL of solution. Solution 1 2 3 4 10 5 Molarity of KSCN 0.00165 M Vol. SCN 5.00 mL 4.00 mL 3.00 mL 2.00 mL Fe³+ +SCN=Fe(SCN)²+ 1.00 mL Molarity of Fe(NO3)3 0.165 M Initial SCN M Fe(SCN)²+ M Absorbance 1.590 1.320 0.990 0.690 0.335

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A From the table you completed in Prelab question 1 from Exp 25 in your lab manual what is the initial SCN concentration for solution 1 Answer The ini... View the full answer