Chapter 5.3, Problem 14E

(a)

Interpretation Introduction

Interpretation: The value of ${\text{K}}_{\text{eq}}$ for the given reaction needs to be determined, if ${\text{pK}}_{\text{as}}$ of phenol and carbonic acid are 10.0 and 6.4 respectively.

Concept Introduction: The pH of buffer solutions can be calculated with the help of Henderson-Hasselbalch equation. The Henderson-Hasselbalch equation can be used that gives the relation between pH and ${\text{pK}}_{\text{a}}$ for weak acids.

  $\begin{array}{l}\text{pH = pKa + log }\frac{\text{[Conjugated base]}}{\text{[Acid]}}\\ \\ \text{pOH = pKb + log }\frac{\text{[Salt]}}{\text{[base]}}\end{array}$

(b)

Interpretation Introduction

Interpretation: The reason of sodium bicarbonate to be a suitable base for separating phenol from a neutral organic compound needs to be explained.

Concept Introduction: The pH of buffer solutions can be calculated with the help of Henderson-Hasselbalch equation. The Henderson-Hasselbalch equation can be used that gives the relation between pH and ${\text{pK}}_{\text{a}}$ for weak acids.

  $\begin{array}{l}\text{pH = pKa + log }\frac{\text{[Conjugated base]}}{\text{[Acid]}}\\ \\ \text{pOH = pKb + log }\frac{\text{[Salt]}}{\text{[base]}}\end{array}$