Chapter U4.19, Problem 4E

(a)

Interpretation Introduction

Interpretation:

The pH of a solution with $\left[{\text{H}}^{+}\right]=0.0014\text{ M}$ needs to be calculated.

Concept Introduction:

The acidity of a solution is expressed in terms of its pH, which is essentially the measure of the hydrogen ion ( ${\text{H}}^{+}$ ) concentration of that solution. Mathematically,

  $\text{pH = }-{\text{log[H}}^{\text{+}}\text{] -----(1)}$

If the pH is below 7, the solution is termed as acidic, if greater than 7, the solution is basic. A neutral solution will have a pH = 7.

Answer to Problem 4E

pH = 2.85

Explanation of Solution

The given hydrogen ion concentration of solution is as follows:

[ ${\text{H}}^{+}$ ] = 0.0014 M

The pH of the solution can be calculated as follows:

   $\begin{array}{c}\text{pH = }-{\text{log[H}}^{\text{+}}\text{] }\end{array}$

    $\begin{array}{c}\text{=}-\text{log[}0.0014\text{] }\end{array}$

    $\begin{array}{c}\text{= 2}\text{.85}\end{array}$

(b)

Interpretation Introduction

Interpretation:

The pH of a solution with $\left[{\text{H}}^{+}\right]=6.0\times {10}^{-8}\text{M}$ needs to be calculated.

Concept Introduction:

The acidity of a solution is expressed in terms of its pH, which is essentially the measure of the hydrogen ion ( ${\text{H}}^{+}$ ) concentration of that solution. Mathematically,

  $\text{pH = }-{\text{log[H}}^{\text{+}}\text{] -----(1)}$

If the pH is below 7, the solution is termed as acidic, if greater than 7, the solution is basic. A neutral solution will have a pH = 7.

Answer to Problem 4E

pH = 7.2

Explanation of Solution

The hydrogen ion concentration in solution is given as follows:

  $\left[{\text{H}}^{+}\right]=6.0\times {10}^{-8}\text{M}$

The pH of the solution can be calculated as follows:

   $\begin{array}{c}\text{pH = }-{\text{log[H}}^{\text{+}}\text{] }\end{array}$

    $\begin{array}{c}\text{=}-\text{log[6}\text{.0}\times {10}^{-8}\text{]}\end{array}$

    $\begin{array}{c}\text{ = 7}\text{.2}\end{array}$

(c)

Interpretation Introduction

Interpretation:

The pH of a solution with $\left[{\text{H}}^{+}\right]=4.2\times {10}^{-11}\text{M}$ needs to be calculated.

Concept Introduction:

The acidity of a solution is expressed in terms of its pH, which is essentially the measure of the hydrogen ion ( ${\text{H}}^{+}$ ) concentration of that solution. Mathematically,

  $\text{pH = }-{\text{log[H}}^{\text{+}}\text{] -----(1)}$

If the pH is below 7, the solution is termed as acidic, if greater than 7, the solution is basic. A neutral solution will have a pH = 7.

Answer to Problem 4E

pH = 10.4

Explanation of Solution

The hydrogen ion concentration in the solution is given as follows:

   $\left[{\text{H}}^{+}\right]=4.2\times {10}^{-11}\text{M}$

The pH of the solution can be calculated as follows:

  $\begin{array}{c}\text{pH = }-{\text{log[H}}^{\text{+}}\text{] }\end{array}$

    $\begin{array}{c}\text{=}-\text{log[4}\text{.2}\times {10}^{-11}\text{]}\end{array}$

    $\begin{array}{c}\text{ = 10}\text{.4}\end{array}$

(d)

Interpretation Introduction

Interpretation:

The pH of a solution with $\left[{\text{H}}^{+}\right]=1.5\times {10}^{-1}\text{M}$ needs to be calculated.

Concept Introduction:

The acidity of a solution is expressed in terms of its pH, which is essentially the measure of the hydrogen ion ( ${\text{H}}^{+}$ ) concentration of that solution. Mathematically,

  $\text{pH = }-{\text{log[H}}^{\text{+}}\text{] -----(1)}$

If the pH is below 7, the solution is termed as acidic, if greater than 7, the solution is basic. A neutral solution will have a pH = 7.

Answer to Problem 4E

pH = 0.82

Explanation of Solution

The hydrogen ion concentration is represented as follows:

  $\left[{\text{H}}^{+}\right]=1.5\times {10}^{-1}\text{M}$

The pH of the solution is calculated as follows:

   $\begin{array}{c}\text{pH = }-{\text{log[H}}^{\text{+}}\text{] }\end{array}$

    $\begin{array}{c}\text{=}-\text{log[1}\text{.5}\times {10}^{-1}\text{]}\end{array}$

    $\begin{array}{c}\text{ =0}\text{.82}\end{array}$