Chapter 14, Problem 62E

Interpretation Introduction

Interpretation: Each of the given solution is to be determined as acidic, basic or neutral.

Concept Introduction: In a neutral solution, the concentrations of both ${\text{H}}_3{\text{O}}^{+}$ and ${\text{OH}}^{-}$ are equal. The concentration of a neutral solution is:

$\begin{array}{c}\left[{\text{H}}_{\text{3}}{\text{O}}^{+}\right]=\left[{\text{OH}}^{-}\right]\\ =1.0\times {10}^{-7}\text{ M}\end{array}$

The concentration of ${\text{H}}_3{\text{O}}^{+}$ ions increases in acidic solution because acidic solution creates additional ${\text{H}}_3{\text{O}}^{+}$ ions. The expression is:

$\begin{array}{c}\left[{\text{H}}_{\text{3}}{\text{O}}^{+}\right]>1.0\times {10}^{-7}\text{ M }\\ \left[{\text{OH}}^{-}\right]<1.0\times {10}^{-7}\text{ M}\end{array}$

The concentration of ${\text{OH}}^{-}$ ions increases in basic solution because basic solution creates additional ${\text{OH}}^{-}$ ions. The expression is:

$\begin{array}{c}\left[{\text{H}}_{\text{3}}{\text{O}}^{+}\right]<1.0\times {10}^{-7}\text{ M }\\ \left[{\text{OH}}^{-}\right]>1.0\times {10}^{-7}\text{ M}\end{array}$