The potassium ion in 250 ml of a water sample was first precipitated as potassium tetraphenylborate: K +(aq) + (C6H5)B- (aq)- KB(C6H5)4 (s). washed, dried and dissolved in an organic solvent. treatment of the organic solution with an excess of aqueous solution of the Hg(ii)-edta complex generated the following reaction: 4HgY2- (aq) +KB(C6H5)4(s) + 4H2O ➜H3BO3, (aq) +4C6H5Hg+(aq) + 4HY3- (aq) + K+ (aq) + OH -(aq) The released edta (in the form of HY3-) was fully titrated with 28.73 ml of 0.04xy mol/l zncl2 solution. Determine the concentration in mg/l of potassium in the water sample. xy is 11

The potassium ion in 250 ml of a water sample was first precipitated as potassium tetraphenylborate: K +(aq) + (C6H5)B- (aq)- KB(C6H5)4 (s). washed, dried and dissolved in an organic solvent. treatment of the organic solution with an excess of aqueous solution of the Hg(ii)-edta complex generated the following reaction: 4HgY2- (aq) +KB(C6H5)4(s) + 4H2O ➜H3BO3, (aq) +4C6H5Hg+(aq) + 4HY3- (aq) + K+ (aq) + OH -(aq) The released edta (in the form of HY3-) was fully titrated with 28.73 ml of 0.04xy mol/l zncl2 solution. Determine the concentration in mg/l of potassium in the water sample. xy is 11

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter26: Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 26.12QAP

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