Fe*(aq) + KSCN(s) →FESCN²+(aq) + K*(aq) To determine the moles of Fe3*(aq) in a 100.0 mL sample of an unknown solution, excess KSCN(s) is added to convert all the Fe3*(aq) species into the dark red species FeSCN²*(aq), as represented by the equation above. The absorbance of FESCN2*(aq) at different concentrations is shown in the graph below. 0.50 0.40 0.30 0.20 0.10 5x 10-5 10 x 10-5 Concentration of FeSCN²* (M) If the absorbance of the mixture is 0.20 at 453 nm, how many moles of Fe3+(aq) were present in the 100.0 mL sample? (Assume that any volume change due to adding KSCN is negligible.) О Зх 106 mol O 4x 104 mol 4x 10-6 mol O 2x 105 mol О 3х 104 mol Absorbance at 453 nm

Fe(aq) + KSCN(s) →FESCN²+(aq) + K(aq) To determine the moles of Fe3(aq) in a 100.0 mL sample of an unknown solution, excess KSCN(s) is added to convert all the Fe3(aq) species into the dark red species FeSCN²(aq), as represented by the equation above. The absorbance of FESCN2(aq) at different concentrations is shown in the graph below. 0.50 0.40 0.30 0.20 0.10 5x 10-5 10 x 10-5 Concentration of FeSCN²* (M) If the absorbance of the mixture is 0.20 at 453 nm, how many moles of Fe3+(aq) were present in the 100.0 mL sample? (Assume that any volume change due to adding KSCN is negligible.) О Зх 106 mol O 4x 104 mol 4x 10-6 mol O 2x 105 mol О 3х 104 mol Absorbance at 453 nm

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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