Low-molecular-weight dicarboxylic acids normally exhibit two different pK, values. Ionization of the first carboxyl group is easier than the second. This effect diminishes with molecular size, and for adipic acid and longer chain dicarboxylic acids, the two acid ionization constants differ by about one pK unit. Dicarboxylic Acid Structural Formula pK,2 a1 Охalic НООССООН 1.23 4.19 Malonic НООСCH,COOH 2.83 5.69 Succinic HOOC(CH,),COOH 4.16 5.61 Glutaric HOOC(CH,),COOH 4.31 5.41 Adipic HOOC(CH,),COOH 4.43 5.41 Why do the two pK, values differ more for the shorter chain dicarboxylic acids than for the longer chain dicarboxylic acids?

Low-molecular-weight dicarboxylic acids normally exhibit two different pK, values. Ionization of the first carboxyl group is easier than the second. This effect diminishes with molecular size, and for adipic acid and longer chain dicarboxylic acids, the two acid ionization constants differ by about one pK unit. Dicarboxylic Acid Structural Formula pK,2 a1 Охalic НООССООН 1.23 4.19 Malonic НООСCH,COOH 2.83 5.69 Succinic HOOC(CH,),COOH 4.16 5.61 Glutaric HOOC(CH,),COOH 4.31 5.41 Adipic HOOC(CH,),COOH 4.43 5.41 Why do the two pK, values differ more for the shorter chain dicarboxylic acids than for the longer chain dicarboxylic acids?

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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