Solution Found!
The pKa of ascorbic acid (vitamin C, page 55) is 4.17, showing that it is slightly more
Chapter 2, Problem 2-54(choose chapter or problem)
The \(\mathrm{p} K_{\mathrm{a}}\) of ascorbic acid (vitamin C, page 55) is 4.17, showing that it is slightly more acidic than acetic acid \(\left(\mathrm{CH}_{3} \mathrm{COOH}\right.,\left.\mathrm{p} K_{\mathrm{a}}\ 4.74\right)\).
(a) Show the four different conjugate bases that would be formed by deprotonation of the four different OH groups in ascorbic acid.
(b) Compare the stabilities of these four conjugate bases, and predict which OH group of ascorbic acid is the most acidic.
(c) Compare the most stable conjugate base of ascorbic acid with the conjugate base of acetic acid, and suggest why these two compounds have similar acidities, even though ascorbic acid lacks the carboxylic acid (COOH) group.
Questions & Answers
QUESTION:
The \(\mathrm{p} K_{\mathrm{a}}\) of ascorbic acid (vitamin C, page 55) is 4.17, showing that it is slightly more acidic than acetic acid \(\left(\mathrm{CH}_{3} \mathrm{COOH}\right.,\left.\mathrm{p} K_{\mathrm{a}}\ 4.74\right)\).
(a) Show the four different conjugate bases that would be formed by deprotonation of the four different OH groups in ascorbic acid.
(b) Compare the stabilities of these four conjugate bases, and predict which OH group of ascorbic acid is the most acidic.
(c) Compare the most stable conjugate base of ascorbic acid with the conjugate base of acetic acid, and suggest why these two compounds have similar acidities, even though ascorbic acid lacks the carboxylic acid (COOH) group.
ANSWER:Step 1 of 3
(a) The structure of ascorbic acid is as follows.
Let’s mark the four hydroxy groups in the ascorbic acid as follows.
The ascorbic acid has four different hydroxy groups .And they formed four conjugate bases by the deprotonation.
The following conjugated bases are formed.
