Chapter 17, Problem 17.18QP

(1)

Interpretation Introduction

Interpretation:

From the given figures, the $\text{pH}$ of the solutions have to be identified.

Concept introduction:

• $\text{pH}\text{=}{\text{pK}}_{\text{a}}\text{+}\text{log}\frac{\text{[conjugate base]}}{\text{[acid]}}$ is Henderson-Hasselbalch equation
• If concentration of conjugate base is larger than weak acid then $\text{pH}>{\text{pK}}_{\text{a}}$
• If concentration of weak acid is larger than conjugate base then $\text{pH}<{\text{pK}}_{\text{a}}$
• Buffer solution is defined as a solution that oppose changes in $\text{pH}$ while adding little amount of either an acid or a base. In general, addition of acid or base does not affect the $\text{pH}$ in buffer solution but if it is more than amount of conjugate base or conjugate acid, then buffer loses its buffering capacity.

(2)

Interpretation Introduction

Interpretation:

From the given figures the $\text{pH}$ of solution $\left(a\right)$ after addition of $\text{0}\text{.1}\text{mol}{\text{H}}^{\text{+}}$ should be calculated.

Concept introduction:

• $\text{pH}\text{=}{\text{pK}}_{\text{a}}\text{+}\text{log}\frac{\text{[conjugate base]}}{\text{[acid]}}$ is Henderson-Hasselbalch equation
• If concentration of conjugate base is larger than weak acid then $\text{pH}>{\text{pK}}_{\text{a}}$
• If concentration of weak acid is larger than conjugate base then $\text{pH}<{\text{pK}}_{\text{a}}$
• Buffer solution is defined as a solution that oppose changes in $\text{pH}$ while adding little amount of either an acid or a base. In general, addition of acid or base does not affect the $\text{pH}$ in buffer solution but if it is more than amount of conjugate base or conjugate acid, then buffer loses its buffering capacity.

(3)

Interpretation Introduction

Interpretation:

From the given figures the $\text{pH}$ of solution $\left(d\right)$ after addition of $\text{0}\text{.1}\text{mol}O{\text{H}}^{\text{-}}$ should be calculated.

Concept introduction:

• $\text{pH}\text{=}{\text{pK}}_{\text{a}}\text{+}\text{log}\frac{\text{[conjugate base]}}{\text{[acid]}}$ is Henderson-Hasselbalch equation
• If concentration of conjugate base is larger than weak acid then $\text{pH}>{\text{pK}}_{\text{a}}$
• If concentration of weak acid is larger than conjugate base then $\text{pH}<{\text{pK}}_{\text{a}}$
• Buffer solution is defined as a solution that oppose changes in $\text{pH}$ while adding little amount of either an acid or a base. In general, addition of acid or base does not affect the $\text{pH}$ in buffer solution but if it is more than amount of conjugate base or conjugate acid, then buffer loses its buffering capacity.