2. You are measuring the Fe(II) content of a sample of FeCl2.4H20. You weighed out1.20g FeCl2.4H20 and dissolved it in 50 mls of 0.5M sulfuric acid. You removed 10ml.s of this solution, mixed it with sulfuric acid and diphenylamine sulfonateindicator, and titrated it to the equivalence point with 0.0167M K2Cr207 solution.You obtained the following data.Volume of dichromate needed to reach the equiv. point = 9.5 ml.sGiven that MeVEe = 6MaiVdi, (where Mre= molarity of the Fe(II) solution, Vre is thevolume of the Fe(II) solution =10 mls. Mai = molarity of the dichromate solution-0.0167M, and Vai = volume of dichromatsolution = 9.5 ml.s), calculate:%3D(a) The molarity of the Fe(Il) solution-M(b) Mass of Fe in the original solution = (Me)(0.05)(55.845) = ------(c) The theoretical mass % Fe in FeCl2.4H20 - -%(d) The experimental mass % Fe in your sample of FeCl2.4H2O----%(e) The % error in your determination of the mass % Fe ---------%

2. You are measuring the Fe(lI) content of a sample of FeCl2.4H20. You weighed out 1.20g FeCl2.4H20 and dissolved it in 50 ml.s of 0.5M sulfuric acid. You removed 10 ml.s of this solution, mixed it with sulfuric acid and diphenylamine sulfonate indicator, and titrated it to the equivalence point with 0.0167M K2Cr207 solution. You obtained the following data. Volume of dichromate needed to reach the equiv. point = 9.5 ml.s Given that MEeVFe 6MaiVai, (where Mre= molarity of the Fe(lI) solution, VEe is the volume of the Fe(II) solution =10 mls. Mai= molarity of the dichromate solution 0.0167M, and Vdi = volume of dichromat solution = 9.5 ml.s), calculate: %3D %3D %3D (a) The molarity of the Fe(Il) solution ----------M (b) Mass of Fe in the original solution = (MF)(0.05)(55.845) = (c) The theoretical mass % Fe in FeCl2.4H20 -----%

2. You are measuring the Fe(lI) content of a sample of FeCl2.4H20. You weighed out 1.20g FeCl2.4H20 and dissolved it in 50 ml.s of 0.5M sulfuric acid. You removed 10 ml.s of this solution, mixed it with sulfuric acid and diphenylamine sulfonate indicator, and titrated it to the equivalence point with 0.0167M K2Cr207 solution. You obtained the following data. Volume of dichromate needed to reach the equiv. point = 9.5 ml.s Given that MEeVFe 6MaiVai, (where Mre= molarity of the Fe(lI) solution, VEe is the volume of the Fe(II) solution =10 mls. Mai= molarity of the dichromate solution 0.0167M, and Vdi = volume of dichromat solution = 9.5 ml.s), calculate: %3D %3D %3D (a) The molarity of the Fe(Il) solution ----------M (b) Mass of Fe in the original solution = (MF)(0.05)(55.845) = (c) The theoretical mass % Fe in FeCl2.4H20 -----%

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.35QAP

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