Chapter 17, Problem 17.4QP

Interpretation Introduction

Interpretation:

By using the value of ${\text{pK}}_{\text{a}}$ of two monoprotic acids, the stronger acid has to be identified.

Concept introduction:

• A quantitative measure of strength of an acid is called acid dissociation constant, ${\text{K}}_{\text{a}}$
• ${\text{pK}}_{\text{a}}$ is defined as logarithm to the base ten of reciprocal of ${\text{K}}_{\text{a}}$.
• ${\text{pK}}_{\text{a}}$ is inversly proportional to acid dissociation constant. Hence increasing ${\text{pK}}_{\text{a}}$ leads to decrease of acid strength and vice-versa.
• Complete dissociation of an acid in a solution is called strong acid.
• An acid which is capable to give one proton per molecule during ionization is called monoprotic acid.
• ${\text{HCl and HNO}}_{\text{3}}$ are monoprotic acids.

To identify: The stronger acid using ${\text{pK}}_{\text{a}}$ values.