Percent Ionization Practice Problems with Solutions

📚 Topic Summary

Percent ionization is a measure of the extent to which an acid or base dissociates into ions in solution. It's calculated as the ratio of the concentration of ions formed to the initial concentration of the acid or base, expressed as a percentage. Understanding percent ionization helps predict the strength of acids and bases and their behavior in chemical reactions.

For a generic acid, HA, the percent ionization is given by:

$Percent\ Ionization = \frac{[A^-]}{[HA]_0} \times 100\%$ where $[A^-]$ is the equilibrium concentration of the conjugate base and $[HA]_0$ is the initial concentration of the acid.

🧪 Part A: Vocabulary

Match the terms with their correct definitions:

Term	Definition
1. Acid	A. A substance that accepts protons.
2. Base	B. The negative logarithm of the acid dissociation constant ($pK_a = -log(K_a)$).
3. Ionization	C. A measure of the extent to which an acid or base dissociates into ions.
4. Percent Ionization	D. The process by which a neutral atom or molecule acquires a positive or negative charge.
5. $pK_a$	E. A substance that donates protons.

📝 Part B: Fill in the Blanks

Complete the following paragraph with the correct words.

Percent ionization is crucial in determining the ________ of an acid or base. It indicates the ________ to which the acid or base dissociates into ________ in a solution. A higher percent ionization suggests a ________ acid or base, meaning it dissociates to a greater extent. The formula to calculate percent ionization involves dividing the ________ concentration of ions by the ________ concentration of the acid or base and multiplying by 100%.

🤔 Part C: Critical Thinking

Explain how percent ionization can be used to compare the strengths of two different weak acids. Provide an example.