Chapter 3, Problem 13RQ

Summary Introduction

Interpretation:

The $\text{p}{K}_{\text{a}}$ and $K_{\text{a}}$ values of the acetic acid is to be determined.

Concept introduction:

The Henderson–Hasselbalch expression for a weak acid and its conjugate base is as follows:

$\text{pH}={\text{pK}}_{\text{a}}+\log \frac{\left[{\text{A}}^{-}\right]}{\left[\text{HA}\right]}$

Here, pH is the measure of the acidity of the solution, $\text{p}{K}_{\text{a}}$ is the negative logarithm of the dissociation constant, $\left[\text{HA}\right]$ is the concentration of weak acid, and $\left[{\text{A}}^{-}\right]$ is the concentration of its conjugate base.

The $\text{p}{K}_{\text{a}}$ value is logarithmic of dissociation constant $K_{\text{a}}$ .

$\text{p}{K}_{\text{a}}\text{= }-\text{log[}{K}_{\text{a}}\text{]}$

Here, $K_{\text{a}}$ is the dissociation constant.