Chapter 20, Problem 20.33AP

Interpretation Introduction

Interpretation:

An explanation regarding the differences in the first and second $\text{p}{K}_{\text{a}}$ values of the dicarboxylic acids which become smaller as lengths of their carbon chains increase is to be stated.

Concept introduction:

The acidity depends on the ease with which the acidic hydrogen is removed and the relative stability of the conjugate base that results after hydrogen is lost. The acidic nature is governed by the electronic nature of the substituent.

Inductive effect is defined as the polarization that results when a shared pair of electrons is attracted by the more electronegative atom bonded in a single bond. It is of two types: $+\text{ I}$ effect and $-\text{I}$ effect.

• $+\text{ I}$ Effect: In this case, the shared pair of electrons is attracted by the electron withdrawing substituents.

• $-\text{I}$ Effect: In this case, electron donating substituents donate their shared pair of electrons.