1) 2,4,6-Trimethylpyridine (also called 2,4,6-collidine) (shown in figure 1) consists of a pyridine ring substituted with three methyl groups. It is often used as a buffer because of its high stability and its biologically relevant pH range. In this problem we will make a buffer with 2,4,6-collidine (pka = 7.43). H3C N. CH3 a) Typically the buffer is prepared from a 0.400M stock solution of 2,4,6-Collidine and 1.00M HCI to adjust the pH. What volume of stock and what volume of titrant would be needed to make 250ml of a buffer with 0.200M total concentration at pH = 7.25? [note: you may also use Dl water to get the correct total volume] CH3

1) 2,4,6-Trimethylpyridine (also called 2,4,6-collidine) (shown in figure 1) consists of a pyridine ring substituted with three methyl groups. It is often used as a buffer because of its high stability and its biologically relevant pH range. In this problem we will make a buffer with 2,4,6-collidine (pka = 7.43). H3C N. CH3 a) Typically the buffer is prepared from a 0.400M stock solution of 2,4,6-Collidine and 1.00M HCI to adjust the pH. What volume of stock and what volume of titrant would be needed to make 250ml of a buffer with 0.200M total concentration at pH = 7.25? [note: you may also use Dl water to get the correct total volume] CH3

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter20: Carboxylic Acids And Nitriles

Section20.3: Biological Acids And The Henderson–hasselbalch Equation

Problem 5P: Calculate the percentages of dissociated and undissociated forms present in the following solutions:...

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