Concept explainers
Using the Ka values in Table 14.2, calculate the percent dissociation in a 0.20-M solution of each of the following acids.
a. nitric acid (HNO3)
b. nitrous acid (HNO2)
c. phenol (HOC6H5)
d. How is percent dissociation of an acid related to the Ka value for the acid (assuming equal initial concentrations of acids)?
(a)
Interpretation:
The percent dissociation of the acid in each of the given solutions is to be calculated.
Concept introduction:
At equilibrium, the equilibrium constant expression is expressed by the formula,
The percent dissociation of an acid is calculated by the formula,
Answer to Problem 74E
(a)
The percent dissociation for the given
(b)
The percent dissociation for the given
(c)
The percent dissociation for the given
(d)
The percent dissociation of an acid is directly proportional to the
Explanation of Solution
To determine: The percent dissociation for a
Therefore, the
Therefore, the
The percent dissociation for the given
The equilibrium concentration of
The initial concentration of
The percent dissociation of an acid is calculated by the formula,
Substitute the value of the concentration of
(b)
Interpretation:
The percent dissociation of the acid in each of the given solutions is to be calculated.
Concept introduction:
At equilibrium, the equilibrium constant expression is expressed by the formula,
The percent dissociation of an acid is calculated by the formula,
Answer to Problem 74E
(a)
The percent dissociation for the given
(b)
The percent dissociation for the given
(c)
The percent dissociation for the given
(d)
The percent dissociation of an acid is directly proportional to the
Explanation of Solution
To determine: The percent dissociation for a
The equilibrium constant expression for the given reaction is,
The dominant equilibrium reaction for the given case is,
At equilibrium, the equilibrium constant expression is expressed by the formula,
Where,
The equilibrium constant expression for the given reaction is,
The
The change in concentration of
The ICE table for the stated reaction is,
The equilibrium concentration of
The equilibrium concentration of
The equilibrium concentration of
The
Substitute the value of
The value of
Simplify the above expression.
Therefore, the
The percent dissociation for the given
The calculated concentration of
The initial concentration of
The percent dissociation of an acid is calculated by the formula,
Substitute the value of the concentration of
(c)
Interpretation:
The percent dissociation of the acid in each of the given solutions is to be calculated.
Concept introduction:
At equilibrium, the equilibrium constant expression is expressed by the formula,
The percent dissociation of an acid is calculated by the formula,
Answer to Problem 74E
(a)
The percent dissociation for the given
(b)
The percent dissociation for the given
(c)
The percent dissociation for the given
(d)
The percent dissociation of an acid is directly proportional to the
Explanation of Solution
To determine: The percent dissociation for a
The equilibrium constant expression for the given reaction is,
The dominant equilibrium reaction for the given case is,
At equilibrium, the equilibrium constant expression is expressed by the formula,
Where,
The equilibrium constant expression for the given reaction is,
The
The change in concentration of
The ICE table for the stated reaction is,
The equilibrium concentration of
The equilibrium concentration of
The equilibrium concentration of
The
Substitute the value of
The value of
Simplify the above expression.
Therefore, the
The percent dissociation for the given
The calculated concentration of
The initial concentration of
The percent dissociation of an acid is calculated by the formula,
Substitute the value of the concentration of
(d)
Interpretation:
The percent dissociation of the acid in each of the given solutions is to be calculated.
Concept introduction:
At equilibrium, the equilibrium constant expression is expressed by the formula,
The percent dissociation of an acid is calculated by the formula,
Answer to Problem 74E
(a)
The percent dissociation for the given
(b)
The percent dissociation for the given
(c)
The percent dissociation for the given
(d)
The percent dissociation of an acid is directly proportional to the
Explanation of Solution
To determine: The relation of percent dissociation of an acid and the
The percent dissociation of an acid is directly proportional to the
The
The percent dissociation of
The
The percent dissociation of
The
The percent dissociation of
Therefore, it can be stated that the percent dissociation of an acid increases with an increase in the
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Chapter 14 Solutions
Chemistry
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Essential Organic Chemistry (3rd Edition)
Chemistry & Chemical Reactivity
Chemistry For Changing Times (14th Edition)
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