Chapter 16, Problem 44QAP

Interpretation Introduction

(a)

Interpretation:

pH corresponding to ${\left[OH\right]}^{-}=8.63\times {10}^{-3}M$ is to be calculated and whether the solution is acidic, basic or neutral is to be indicated.

Concept Introduction:

• pH is a logarithmic scale which specify the acidity or basicity of the solution.

  $pH=-\log [H^{+}]$

  $\begin{array}{l}pOH=-log{\left[OH\right]}^{-}\\ pH+pOH=14\end{array}$

• Neutral solution- A solution is neutral if $pH=7$
• Acidic solution- A solution is acidic if $pH<7$
• Basic solution- A solution is basic if $pH>7$

Answer to Problem 44QAP

pH = 11.94 so, the solution is basic in nature.

Explanation of Solution

As ${\left[OH\right]}^{-}=8.63\times {10}^{-3}M$

  $\begin{array}{l}pH+pOH=14\hfill \\ pH=14-\left(-log{\left[OH\right]}^{-}\right)\hfill \\ pH=14–\left(-log8.63\times {10}^{-3}M\right)\hfill \\ pH=14–2.06\hfill \\ pH=11.94\hfill \end{array}$

Thus, pH is greater than 7 which implies that the given solution is basic in nature.

Interpretation Introduction

(b)

Interpretation:

pH corresponding to ${\left[OH\right]}^{-}=7.44\times {10}^{-6}M$ is to be calculated and whether the solution is acidic, basic or neutral is to be indicated.

Concept Introduction:

• pH is a logarithmic scale which specify the acidity or basicity of the solution.

  $pH=-\log [H^{+}]$

  $\begin{array}{l}pOH=-log{\left[OH\right]}^{-}\\ pH+pOH=14\end{array}$

• Neutral solution- A solution is neutral if $pH=7$
• Acidic solution- A solution is acidic if $pH<7$
• Basic solution- A solution is basic if $pH>7$

Answer to Problem 44QAP

pH = 8.87 so, the solution is basic in nature.

Explanation of Solution

As ${\left[OH\right]}^{-}=7.44\times {10}^{-6}M$

  $\begin{array}{l}\begin{array}{l}pH+pOH=14\hfill \\ pH=14-\left(-log{\left[OH\right]}^{-}\right)\hfill \\ pH=14–\left(-log7.44\times {10}^{-6}M\right)\hfill \\ pH=14–5.13\hfill \end{array}\\ pH=8.87\end{array}$

Thus, pH is greater than 7 which implies that the given solution is basic in nature.

Interpretation Introduction

(c)

Interpretation:

pH corresponding to ${\left[OH\right]}^{-}=9.35\times {10}^{-9}M$ is to be calculated and whether the solution is acidic, basic or neutral is to be indicated.

Concept Introduction:

• pH is a logarithmic scale which specify the acidity or basicity of the solution.

  $pH=-\log [H^{+}]$

  $\begin{array}{l}pOH=-log{\left[OH\right]}^{-}\\ pH+pOH=14\end{array}$

• Neutral solution- A solution is neutral if $pH=7$
• Acidic solution- A solution is acidic if $pH<7$
• Basic solution- A solution is basic if $pH>7$

Answer to Problem 44QAP

pH = 5.97 so, the solution is acidic in nature.

Explanation of Solution

As ${\left[OH\right]}^{-}=9.35\times {10}^{-9}M$

  $\begin{array}{l}pH+pOH=14\hfill \\ pH=14-\left(-log{\left[OH\right]}^{-}\right)\hfill \\ pH=14–\left(-log9.35\times {10}^{-9}M\right)\hfill \\ pH=14–8.03\hfill \\ pH=5.97\hfill \end{array}$

Thus, pH is less than 7 which implies that the given solution is acidic in nature.

Interpretation Introduction

(d)

Interpretation:

pH corresponding to ${[OH]}^{-}=1.21\times {10}^{-11}M$ is to be calculated and whether the solution is acidic, basic or neutral is to be indicated.

Concept Introduction:

• pH is a logarithmic scale which specify the acidity or basicity of the solution.

  $pH=-\log [H^{+}]$

  $\begin{array}{l}pOH=-log{\left[OH\right]}^{-}\\ pH+pOH=14\end{array}$

• Neutral solution- A solution is neutral if $pH=7$
• Acidic solution- A solution is acidic if $pH<7$
• Basic solution- A solution is basic if $pH>7$

Answer to Problem 44QAP

pH = 3.08 so, the solution is acidic in nature.

Explanation of Solution

As ${\left[OH\right]}^{-}=1.21\times {10}^{-11}M$

  $\begin{array}{l}pH+pOH=14\hfill \\ pH=14-\left(-log{\left[OH\right]}^{-}\right)\hfill \\ pH=14–\left(-log1.21\times {10}^{-11}M\right)\hfill \\ pH=14–10.92\hfill \\ pH=3.08\hfill \end{array}$

Thus, pH is less than 7 which implies that the given solution is acidic in nature.