Chapter 15, Problem 113QRT

Interpretation Introduction

Interpretation:

The $\text{pH}$ of the solution after addition of acid has to be calculated.

Concept Introduction:

Molarity is defined as the ratio of number of moles of solute to the volume of solution is liters.  The S.I. unit if molarity is molar and it is represented by $\text{M}$.

Mathematical formulation of molarity is shown below.

  $\text{Molarity }=\frac{\text{Moles of solute}}{\text{Volume of solution }\left(\text{L}\right)}$

The Henderson-Hasselbalch equation can be used to determine the $\text{pH}$ of the buffer which is formed by the known concentrations of conjugate base and conjugate acid. This equation can also be applied to calculate the ratio of conjugate base to conjugate acid concentration.

The Henderson-Hasselbalch equation can be represented as shown below.

  $\text{pOH }={\text{pK}}_{\text{b}}+\log \frac{\left[\text{conjugate}\text{acid}\right]}{\left[\text{conjugate}\text{base}\right]}$