Textbook Question
Calculate the percent ionization of a formic acid solution having the given concentration. c. 0.100 M
Ch.17 - Acids and Bases
Chapter 17, Problem 76
A 0.085 M solution of a monoprotic acid has a percent ionization of 0.59%. Determine the acid ionization constant (Ka) for the acid.
Verified step by step guidance1
insert step 1> Calculate the concentration of ionized acid using the percent ionization formula: \( \text{Percent Ionization} = \left( \frac{[\text{H}^+]}{[\text{HA}]} \right) \times 100 \). Here, [HA] is the initial concentration of the acid, and [H+] is the concentration of ionized acid.
insert step 2> Rearrange the formula to solve for [H+]: \( [\text{H}^+] = \frac{\text{Percent Ionization} \times [\text{HA}]}{100} \).
insert step 3> Substitute the given values into the equation: \( [\text{H}^+] = \frac{0.59 \times 0.085}{100} \).
insert step 4> Write the expression for the acid ionization constant \( K_a \) for a monoprotic acid: \( K_a = \frac{[\text{H}^+][\text{A}^-]}{[\text{HA}]} \). Since the acid is monoprotic, [H+] = [A-].
insert step 5> Substitute the values into the \( K_a \) expression: \( K_a = \frac{([\text{H}^+])^2}{[\text{HA}] - [\text{H}^+]} \). Use the calculated [H+] and initial [HA] to find \( K_a \).
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Monoprotic Acid
A monoprotic acid is an acid that can donate only one proton (H+) per molecule during the ionization process. This characteristic simplifies the calculation of its ionization in solution, as it only involves the dissociation of a single hydrogen ion. Common examples include acetic acid and hydrochloric acid.
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Binary Acids
Percent Ionization
Percent ionization is a measure of the extent to which an acid dissociates in solution, expressed as a percentage. It is calculated by dividing the concentration of ionized acid by the initial concentration of the acid, then multiplying by 100. This concept helps in understanding the strength of the acid; a higher percent ionization indicates a stronger acid.
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Acid Ionization Constant (Ka)
The acid ionization constant (Ka) quantifies the strength of an acid in solution, representing the equilibrium constant for the dissociation of the acid into its ions. It is calculated using the concentrations of the products and reactants at equilibrium. A larger Ka value indicates a stronger acid, as it implies a greater degree of ionization.
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Related Practice
Textbook Question
Calculate the percent ionization of a formic acid solution having the given concentration. d. 0.0500 M
Textbook Question
A 0.148 M solution of a monoprotic acid has a percent ionization of 1.55%. Determine the acid ionization constant (Ka) for the acid.
Textbook Question
Find the pH of each mixture of acids. a. 0.115 M in HBr and 0.125 M in HCHO2