ACIDS AND BASES AP CHEMISTRY REVIEW DEMONSTRATION KIT

Product Details

The following topics are listed for acids and bases by the College Board: concepts of Arrhenius, Brønsted–Lowry and Lewis, coordination complexes, amphoterism, pK_a and pH, buffers and hydrolysis. Use this set of three acid–base demonstrations to both engage students in a hands-on review and test their understanding. Enough materials are included to perform each demonstration twice.
• Weak Base–Weak Acid Titration—Start the review with a titration of a weak acid with a weak base. What is the pH at the endpoint? Students graph pH versus volume of base added. Based on the graph and their knowledge of end-point pH calculations, students determine the relative strengths of the acid and the base.
• Acid Mixture, Concentration and K_a—A mixture of hydrochloric acid and maleic acid is titrated with sodium hydroxide. Students graph the titration curve and use the data to determine the concentration of each acid in the mixture and the K_a of maleic acid.
• Acid Strength and Electron-Withdrawing Groups—Show the trend for K_a of acetic acid and its mono- and tri-chloride substitutions. Students explain this trend based on these values and their knowledge of electron affinity.

Concepts: Weak acids and bases, conjugate acids and bases, equilibrium constant, K_a, and K_b, pH, and inductive effect.
Time Required: One class period.
Chemicals Provided: Acetic acid solution, ammonia solution, bromphenol blue indicator solution, chloroacetic acid solution, hydrochloric acid solution, maleic acid, methyl red indicator solution, orange IV indicator solution, phenolphthalein indicator solution, sodium hydroxide solution, trichloroacetic acid, universal indicator solution. A pH meter is required and available separately.