Three extractions with 50 ml portions of chloroform removed 97% of a solute from 200ml of an aqueous solution. Calculate the partition coefficient of the solute:KD =Cchloro/Caq-Two weak bases (organic amities) have basic dissociation constants of KbA= 1 x 104and KbB =1 x 10-8. Both bases have partition coefficients of approximately 10 betweenchloroform and water. Describe a procedure, making use of the difference in K, forseparating the two by extraction.Two weak acids, HX and HY, have partition coefficients, Kp = Cet/Caq, of 5 and 50respectively, and dissociation constants of 1 x 104 and 1 x 108, respectively. Calculatethe distribution ratios of the two acids at integral values of pH of the aqueous solutionfrom pH 4 to pH 11, assuming equal volumes of the two solvents. What is the minimumpH for which the ratio of D values is at least 105?

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Three extractions with 50 ml portions of chloroform removed 97% of a solute from 200 ml of an aqueous solution. Calculate the partition coefficient of the solute: KD=Cchioro/Caq- Two weak bases (organic amities) have basic dissociation constants of KbA= 1 x 10-4 and KbB = 1 x 108. Both bases have partition coefficients of approximately 10 between chloroform and water. Describe a procedure, making use of the difference in kb, for separating the two by extraction. Two weak acids, HX and HY, have partition coefficients, KD = Cet/Caq, of 5 and 50 respectively, and dissociation constants of 1 x 104 and 1 x 10-8, respectively. Calculate the distribution ratios of the two acids at integral values of pH of the aqueous solution from pH 4 to pH 11, assuming equal volumes of the two solvents. What is the minimum pH for which the ratio of D values is at least 105?

Three extractions with 50 ml portions of chloroform removed 97% of a solute from 200 ml of an aqueous solution. Calculate the partition coefficient of the solute: KD=Cchioro/Caq- Two weak bases (organic amities) have basic dissociation constants of KbA= 1 x 10-4 and KbB = 1 x 108. Both bases have partition coefficients of approximately 10 between chloroform and water. Describe a procedure, making use of the difference in kb, for separating the two by extraction. Two weak acids, HX and HY, have partition coefficients, KD = Cet/Caq, of 5 and 50 respectively, and dissociation constants of 1 x 104 and 1 x 10-8, respectively. Calculate the distribution ratios of the two acids at integral values of pH of the aqueous solution from pH 4 to pH 11, assuming equal volumes of the two solvents. What is the minimum pH for which the ratio of D values is at least 105?

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter28: High-performance Liquid Chromatography

Section: Chapter Questions

Problem 28.2QAP

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