Concept explainers
(a)
Interpretation:
The ratio of A- to [HA] with the help of pH and pKa values should be calculated.
Concept Introduction:
The pH of a solution indicates the number of H3 O+ ions in the solution. The mathematical relation between pH and H3 O+ is as given below;.
Acid dissociation constant Ka is related to pKa as;.
Answer to Problem 30P
Explanation of Solution
Given Information:
pKa = 5.0.
pH = 2.0.
Calculation:
From pH of solution, concentration of hydroxide ion can be calculated as follows:
Also,
Since,
Thus, by putting the values, the ratio
(b)
Interpretation:
The ratio of A- to [HA] with the help of pH and pKa values should be calculated.
Concept Introduction:
The pH of a solution indicates the number of H3 O+ ions in the solution. The mathematical relation between pH and H3 O+ is as given below;.
Acid dissociation constant Ka is related to pKa as;.
Answer to Problem 30P
Given:
pKa = 5.0.
pH = 5.0.
Hence [H3 O+ ] = 10-pH = 10-5.
And Ka = 10-pKa = 10-5.
Since
Plug the values of Ka and H3 O+ ions to calculate the ratio of [A- ] to [HA].
[A- ] / [HA] = 10-5 / 10-5 = 1.
Explanation of Solution
Given Information:
pKa = 5.0.
pH = 5.0.
Calculation:
From pH of solution, concentration of hydroxide ion can be calculated as follows:
Also,
Since,
Thus, by putting the values, the ratio
(c)
Interpretation:
The ratio of A- to [HA] with the help of pH and pKa values should be calculated.
Concept Introduction:
The pH of a solution indicates the number of H3 O+ ions in the solution. The mathematical relation between pH and H3 O+ is as given below;.
Acid dissociation constant Ka is related to pKa as;.
Answer to Problem 30P
Explanation of Solution
Given Information:
pKa = 5.0.
pH = 7.0.
Calculation:
From pH of solution, concentration of hydroxide ion can be calculated as follows:
Also,
Since,
Thus, by putting the values, the ratio
(d)
Interpretation:
The ratio of A- to [HA] with the help of pH and pKa values should be calculated.
Concept Introduction:
The pH of a solution indicates the number of H3 O+ ions in the solution. The mathematical relation between pH and H3 O+ is as given below;.
Acid dissociation constant Ka is related to pKa as;.
Answer to Problem 30P
Explanation of Solution
Given Information:
pKa = 5.0.
pH = 9.0.
Calculation:
From pH of solution, concentration of hydroxide ion can be calculated as follows:
Also,
Since,
Thus, by putting the values, the ratio
(e)
Interpretation:
The ratio of A- to [HA] with the help of pH and pKa values should be calculated.
Concept Introduction:
The pH of a solution indicates the number of H3 O+ ions in the solution. The mathematical relation between pH and H3 O+ is as given below;.
Acid dissociation constant Ka is related to pKa as;.
Answer to Problem 30P
Explanation of Solution
Given Information:
pKa = 5.0.
pH = 11.0.
Calculation:
From pH of solution, concentration of hydroxide ion can be calculated as follows:
Also,
Since,
Thus, by putting the values, the ratio
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Chapter 17 Solutions
Introduction to General, Organic and Biochemistry
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