Calculate percent ionization and concentration ratios, or use an ideal 25 °C single-step acid/base model to relate Ka, Kb, pKa, pKb, concentration and pH or pOH.

Ideal aqueous 1:1 single-step model at 25 °C, with Kw = 10⁻¹⁴. No buffers, common-ion additions, activity corrections or later polyprotic steps are modeled.

Related Calculators

Ionization Percent Formula

The following formula is used to calculate the ionization percent for a given concentration of ionized acid and initial concentration of acid.

P = (Cᵢ / C₀) × 100

Variables:

  • P is the ionization percent
  • C_i is the concentration of ionized acid (M)
  • C_0 is the initial concentration of acid (M)

To calculate the ionization percent from measured dissociation, divide the dissociated amount per solution volume by the initial analytical concentration and multiply by 100. In the isolated ideal acid/base modes, water autoionization is included: x = y − Kw/y and K = xy/(C − x), where y is [H₃O⁺] for an acid or [OH⁻] for a base and Kw = 10⁻¹⁴ at 25 °C. Total measured ion concentration is not identical to acid/base dissociation near neutrality.

What is Ionization Percent?

Ionization percent is a measure of the extent to which an acid ionizes in a solution. It is expressed as a percentage and indicates the ratio of the concentration of ionized acid to the initial concentration of acid. This value is important in understanding the strength and behavior of acids in various chemical reactions and solutions.

How to Calculate Ionization Percent?

The following steps outline how to calculate the Ionization Percent.

  1. First, determine the concentration of ionized acid (C_i).
  2. Next, determine the initial concentration of acid (C_0).
  3. Next, calculate the ionization percent using the formula P = (C_i / C_0) * 100.
  4. Select the matching solve mode, enter the requested values and select Calculate.
  5. After inserting the values and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Concentration of ionized acid (C_i) = 0.02 M

Initial concentration of acid (C_0) = 0.1 M. The measured dissociation ratio is 0.02 / 0.1 × 100 = 20%. This ratio by itself does not establish pH or Ka.