AP-aligned particulate diagram practice with multiple-choice and free-response items, including a draw-it-yourself FRQ and pH/pKa buffer reasoning. Built by a Ph.D. chemist. This 20-question particulate diagram practice set was built specifically to mirror the AP Chemistry exam's current format — including the recent shift toward draw-the-diagram FRQs and pH/pKa buffer reasoning that has dominated free-response sections since 2023. Your students get 14 carefully calibrated multiple-choice items