Chapter 6, Problem 6B.7E

(a)

Interpretation Introduction

Interpretation:

Molar concentration of hydronium ions in orange juice has to be given if the $\text{pH}$ of orange juice is $3.3$.

Concept Introduction:

Negative logarithm of the concentration of hydronium ion is the $\text{pH}$ of solution.  This can be given in equation form as follows;

    $\text{pH}=-\log [{\text{H}}_{\text{3}}{\text{O}}^{\text{+}}]$

From the above equation, the concentration of hydronium ions can be calculated by rearranging.  The sign of $\text{pH}$ is reversed and antilogarithm of the $\text{pH}$ is taken in order to obtain the concentration of hydronium ions.  This can be expressed in equation form as follows;

    $[{\text{H}}_{\text{3}}{\text{O}}^{\text{+}}]={10}^{-\text{pH}}\text{mol}\cdot {\text{L}}^{-1}$

(b)

Interpretation Introduction

Interpretation:

Molar concentration of hydronium ions in saliva sample has to be given if the $\text{pH}$ of saliva sample is $6.7$.

Concept Introduction:

Refer part (a).

(c)

Interpretation Introduction

Interpretation:

Molar concentration of hydronium ions in beer has to be given if the $\text{pH}$ of beer is $4.4$.

Concept Introduction:

Refer part (a).

(d)

Interpretation Introduction

Interpretation:

Molar concentration of hydronium ions in coffee sample has to be given if the $\text{pH}$ of coffee sample is $5.3$.

Concept Introduction:

Refer part (a).