You have a 20 mL sample of acetylcholine (a neurotransmitter) with an unknown concentration and a pH of 8.17. You incubate this sample with the enzyme acetylcholinesterase to convert all of the acetylcholine to choline and acetic acid. The acetic acid dissociates to yield acetate and hydrogen ions. At the end of the incubation period, you measure the pH again and find that it has decreased to 6.70. Assuming there was no buffer in the assay mixture, determine the number of nanomoles of acetylcholine in the original 20 mL sample. Acetylcholine CH₂ H₂O 1-0-CH₂ CH,—C−O−CH,−CH,−NCH, → HO–CH,—CH,—*N–CH, HO–CH,—CH,—*N–CH, + CH,-C−O + H* CH₂--0- acetycholine in original sample: I CH, CH₂ I Choline I CH₂ Acetate nmol

You have a 20 mL sample of acetylcholine (a neurotransmitter) with an unknown concentration and a pH of 8.17. You incubate this sample with the enzyme acetylcholinesterase to convert all of the acetylcholine to choline and acetic acid. The acetic acid dissociates to yield acetate and hydrogen ions. At the end of the incubation period, you measure the pH again and find that it has decreased to 6.70. Assuming there was no buffer in the assay mixture, determine the number of nanomoles of acetylcholine in the original 20 mL sample. Acetylcholine CH₂ H₂O 1-0-CH₂ CH,—C−O−CH,−CH,−NCH, → HO–CH,—CH,—N–CH, HO–CH,—CH,—N–CH, + CH,-C−O + H* CH₂--0- acetycholine in original sample: I CH, CH₂ I Choline I CH₂ Acetate nmol

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter15: Additional Aqueous Equilibria

Section: Chapter Questions

Problem 17QRT: Without doing calculations, determine the pH of a buffer made front equimolar amounts of these...

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