This is an in-class activity that introduces students to the concepts of ionization of strong and weak acids in aqueous solutions and equilibrium constants for acid ionization using two of the domains in Johnstone's triangle of chemistry knowledge, submicroscopic particle level illustrations and symbolic representations.
The learning goals for this activity are to:
1. introduce students to the concept of ionization of strong and weak acids in aqueous solutions,
2. help students compare ionization of strong versus weak acids,
3. introduce students to the equilibrium constant for ionization of an acid and correlate this equilibrium constant to acid strength,
4. allow students to practice calculating the pH of aqueous solutions containing strong and weak acids,
5. introduce students to the concept of percent ionization of a weak acid.
None besides pencil and printed worksheets
In my classes, students work on this activity in groups of 3-4 during one of the weekly discussion meetings. This activity typically takes students 45-50 minutes. For shorter class periods, the section on percent ionization could be eliminated. "RICE tables" refer to tables with rows to keep track of the (r)eaction and (i)nitial, (c)hange, and (e)quilibrium concentrations. Sometimes these are referred to as ICE tables.
Evaluation was conducted via exam questions involving ionization of strong and weak acids in aqueous solutions.
Scores on the exam questions ranged from 70%-90%.