Chapter 17, Problem 9QP

Interpretation Introduction

Interpretation:

The pH of the buffer solution of ${\text{NH}}_{\text{3}}$ and ${\text{NH}}_{\text{4}}\text{Cl}$ is to be calculated.

Concept introduction:

A bufferis a solutionthat resists the change in pH on the addition of the acid and alkali. It consists of a mixture of a weak acid with its conjugate base or a weak base with its conjugate acid.

The pH of a buffer solution is calculated by the Henderson–Hasselbalach equation, which is as follows:

For the acidic buffer $\text{pH}=\text{p}{K}_{\text{a}}+\text{log}\frac{\text{[Conjugate Base]}}{\text{[Weak Acid]}}$

For the basic buffer $\text{pH}=\text{p}{K}_{\text{a}}+\text{log}\frac{\text{[Weak Base]}}{\text{[Conjugate Acid]}}$