Exhibit 20-1 Consider the data in the Table below to answer the following questi

Question

Exhibit 20-1
Consider the data in the Table below to answer the following question(s):

Acidities of Substituted Benzoic and Acetic Acids

pKas at 25°C

YC6H4COOH

Y

YCH2COOH

meta

para

H

4.75

4.19

4.19

CN

2.47

3.64

3.55

OCH3

3.57

4.09

4.46

13. Refer to Exhibit 20-1. Draw the structure of the strongest acid in the table above.

14. Refer to Exhibit 20-1. Which of the acids in the table above has the strongest conjugate base?

15. Refer to Exhibit 20-1. Explain why cyanoacetic acid and methoxyacetic acid are more acidic than their correspondingly substituted benzoic acid counterparts.

Exhibit 20-1
Consider the data in the Table below to answer the following question(s):

Acidities of Substituted Benzoic and Acetic Acids

pKas at 25°C

YC6H4COOH

Y

YCH2COOH

meta

para

H

4.75

4.19

4.19

CN

2.47

3.64

3.55

OCH3

3.57

4.09

4.46

Explanation / Answer

Hi Dear Friend, your answers are here below.

13. NCCH2COOH  

Reason: smaller the pKa stronger the acidic character.

14. CH3COOH  

Reason: Higher pKa value represents weak acid, weak acids conjugate bases are always stronger.

15. Electron-withdrawing groups, like CN and OCH3, inductively withdraw electron density, which stabilizes the resulting carboxylate anion and, thus, increases the acidity of the carboxylic acid. These inductive effects are strongly dependent on distance. The CN and OCH3 substituents are closer to the carboxylate in the substituted acetic acids than in the substituted benzoic acids, so their effect is greater.

Hope this helped you!

Thank You So Much! Please Rate this answer as you wish.("Thumbs Up")

Related Questions

Navigate

• Browse (All)
• Browse E
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.