A 25.00-mL sample of La31 was treated with excess Na2C2O4 to precipitate La2(C2O4)3, which was washed to remove excess C2O4 22 and then dissolved in acid. The oxalate from La2(C2O4)3 required 12.34 mL of 0.004 321 M KMnO4 to reach the purple end point of Reaction 6-1. Find the molarity of La31 in the unknown.

A 25.00-mL sample of La31 was treated with excess Na2C2O4 to precipitate La2(C2O4)3, which was washed to remove excess C2O4 22 and then dissolved in acid. The oxalate from La2(C2O4)3 required 12.34 mL of 0.004 321 M KMnO4 to reach the purple end point of Reaction 6-1. Find the molarity of La31 in the unknown.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.22QAP

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