An interesting and challenging problem for AP Chemistry students is the investigation of a mixture. We offer a chemistry experiment in which the student analyzes a mixture of hydrochloric acid, HCl, and phosphoric acid, H3PO4. The student is presented with the task of conducting a seemingly routine acid-base titration. However, the student must analyze the titration data to determine how much HCl and how much H3PO4 were in the mixture. As an added bonus, the student will determine the Ka2 of H3PO4.
Titration of an HCl-H3PO4 Mixture