The concentration of acetylcholine (a neurotransmitter) in a sample can be determined from the pH changes that accompany its hydrolysis. When the sample is incubated with the enzyme acetylcholinesterase, acetylcholine is converted to choline and acetic acid, which dissociates to yield acetate and a hydrogen ion. CНз CHз Нао — сHz— CH "N— снз но-сн— сH,-"N-CH; + CH;— с-о+ н* CH3-C-0- сHз CHз Choline Acetylcholine Acetate In a typical analysis, 11 mL of an aqueous solution containing an unknown amount of acetylcholine had a pH of 7.70. When incubated with acetylcholinesterase, the pH of the solution decreased to 6.89. Assuming there was no buffer in the assay mixture, determine the number of moles of acetylcholine in the 11 mL sample.

The concentration of acetylcholine (a neurotransmitter) in a sample can be determined from the pH changes that accompany its hydrolysis. When the sample is incubated with the enzyme acetylcholinesterase, acetylcholine is converted to choline and acetic acid, which dissociates to yield acetate and a hydrogen ion. CНз CHз Нао — сHz— CH "N— снз но-сн— сH,-"N-CH; + CH;— с-о+ н* CH3-C-0- сHз CHз Choline Acetylcholine Acetate In a typical analysis, 11 mL of an aqueous solution containing an unknown amount of acetylcholine had a pH of 7.70. When incubated with acetylcholinesterase, the pH of the solution decreased to 6.89. Assuming there was no buffer in the assay mixture, determine the number of moles of acetylcholine in the 11 mL sample.

Chemistry & Chemical Reactivity

9th Edition

ISBN:9781133949640

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter16: Principles Of Chemical Reactivity: The Chemistry Of Acids And Bases

Section: Chapter Questions

Problem 116IL: Amino acids are an important group of compounds. At low pH, both the carboxylic acid group (CO2H)...

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