Chapter 18, Problem 18.91P

(a)

Interpretation Introduction

Interpretation:

The lower $\text{pH}$ of the solution has to be identified from the given pairs, $\text{ 0}{\text{.5 M CuBr}}_{\text{2}}\text{ or 0}{\text{.5 M AlBr}}_{\text{3}}$.

Concept introduction:

Increasing acid strength:

Acids strength is mainly depending on the dissociation of ions, strong acids dissociates completely and weak acid dissociate slightly.

The acid strength is depending on the ${\text{K}}_{\text{a}}$ value, if the ${\text{K}}_{\text{a}}$ value is larger the stronger the acid and it is lower $\text{pH}$.

(b)

Interpretation Introduction

Interpretation:

The lower $\text{pH}$ of the solution has to be identified from the given pairs $\text{ 0}{\text{.3 M ZnCl}}_{\text{2}}\text{ or 0}{\text{.3 M SnCl}}_{\text{2}}$.

Concept introduction:

Increasing acid strength:

Acids strength is mainly depending on the dissociation of ions, strong acids dissociates completely and weak acid dissociate slightly.

The acid strength is depending on the ${\text{K}}_{\text{a}}$ value, if the ${\text{K}}_{\text{a}}$ value is larger the stronger the acid and it is lower $\text{pH}$.