35. For each pair of concentrations, tell which represents the more acidic solution.

a. [ H + ] = 1.2 × 10 − 3 M  or  [ H + ] = 4.5 × 10 − 4 M

b. [ H + ] = 2.6 × 10 − 6 M  or  [ H + ] = 4.3 × 10 − 8 M

c. [ H + ] = 0.000010 M  or  [ H + ] = 0.0000010

(a)

Interpretation:

The more acidic solution should be determined.

Concept Introduction:

The concentration of hydrogen ions in a solution determines the acidity of a solution. If concentration of hydrogen ion is more than the solution is more acetic, if it is low, solution is less acidic.

The pH of solution is defined as negative log of hydrogen ion concentration thus, it can be calculated as follows:

pH=−log[H+]

Here, [H+] is concentration of hydrogen ion.

Similarly, pOH of a solution is defined as negative log of hydroxide ion concentration thus, it can be calculated as follows:

pOH=−log[OH−]

Here, [OH−] is concentration of hydroxide ion.

pH and pOH of a solution are related to each other as follows:

pH+pOH=14

In a pH scale, if the value of pH is below 7 the solution is said to be acidic in nature, if the Ph value is above 7 it is said to be basic in nature. At pH 7, the solution is neutral.

Given Information:

[H+]=1.2×10−3 M or [H+]=4.5×10−4 M

Calculation:

The pH of solutions should be calculated to compare the acidity of the solutions.

Solution 1, the concentration of hydrogen ion is 1.2×10−3 M thus, pH of solution can be calculated as follows:

pH=−log(1.2×10−3)=2

(b)

Interpretation:

The more acidic solution should be determined.

Concept Introduction:

The concentration of hydrogen ions in a solution determines the acidity of a solution. If concentration of hydrogen ion is more than the solution is more acetic, if it is low, solution is less acidic.

The pH of solution is defined as negative log of hydrogen ion concentration thus, it can be calculated as follows:

pH=−log[H+]

Here, [H+] is concentration of hydrogen ion.

Similarly, pOH of a solution is defined as negative log of hydroxide ion concentration thus, it can be calculated as follows:

pOH=−log[OH−]

Here, [OH−] is concentration of hydroxide ion.

pH and pOH of a solution are related to each other as follows:

pH+pOH=14

In a pH scale, if the value of pH is below 7 the solution is said to be acidic in nature, if the Ph value is above 7 it is said to be basic in nature. At pH 7, the solution is neutral.

(c)

Interpretation:

The more acidic solution should be determined.

Concept Introduction:

The concentration of hydrogen ions in a solution determines the acidity of a solution. If concentration of hydrogen ion is more than the solution is more acetic, if it is low, solution is less acidic.

The pH of solution is defined as negative log of hydrogen ion concentration thus, it can be calculated as follows:

pH=−log[H+]

Here, [H+] is concentration of hydrogen ion.

Similarly, pOH of a solution is defined as negative log of hydroxide ion concentration thus, it can be calculated as follows:

pOH=−log[OH−]

Here, [OH−] is concentration of hydroxide ion.

pH and pOH of a solution are related to each other as follows:

pH+pOH=14

In a pH scale, if the value of pH is below 7 the solution is said to be acidic in nature, if the Ph value is above 7 it is said to be basic in nature. At pH 7, the solution is neutral.