Chapter 3, Problem 5Q

Interpretation Introduction

Interpretation:

The strongest acid of the following reagents is to be determined.

Concept introduction:

$\text{p}{K}_{\text{a}}$ of a reagent can be mathematically defined as follows:

$\text{p}{K}_{\text{a}}\text{= }-\text{log(}{K}_{\text{a}}\text{) }$, where $K_{\text{a}}$ is the dissolution constant …… (1)

More the dissolution constant, more are the ions produced when the reagent is dissolved in water. Thus, by the above relation, strong acids have low $\text{p}{K}_{\text{a}}$.

Electronegative atoms such as halides or oxygen or sulfur have an electron withdrawing inducive effect which helps in losing an acidic proton more readily thus increasing the acidity of the organic compound.

The electron withdrawing inducive force is inversely proportional to the distance between the acidic proton and the electronegative element.

The electron withdrawing inducive force is directly proportional to the electronegativity of the element. More the electronegativity of the element more is the negative charge stabilized and more is the acidity.