13. A sample contained Cr(III) species. A 25.00 mL portion of this sample is combined with 10.00 mL of a 0.0875 M solution that contains a complexing agent, CDTA. This mixture is heated to boiling for several minutes to allow the CDTA to complex with Cr(III) species. The mixture is then cooled, and the excess CDTA is measured by a back titration using 0.0258 M Bi³+, required 4.20 mL to reach end point. Determine the original concentration of Cr(III) species in the sample [Molar ratio of CDTA:Cr(III):Bi³+ = 1:1:1]

13. A sample contained Cr(III) species. A 25.00 mL portion of this sample is combined with 10.00 mL of a 0.0875 M solution that contains a complexing agent, CDTA. This mixture is heated to boiling for several minutes to allow the CDTA to complex with Cr(III) species. The mixture is then cooled, and the excess CDTA is measured by a back titration using 0.0258 M Bi³+, required 4.20 mL to reach end point. Determine the original concentration of Cr(III) species in the sample [Molar ratio of CDTA:Cr(III):Bi³+ = 1:1:1]

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.34QAP

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