2021 AP Exam Administration Student Samples AP Chemistry Free Response Question 1 2021 AP ® Chemistry Sample Student Responses and Scoring Commentary © 2021 College Board College Board, Advanced Place[.]
2021 AP Chemistry ® Sample Student Responses and Scoring Commentary Inside: Free Response Question R Scoring Guideline R Student Samples R Scoring Commentary © 2021 College Board College Board, Advanced Placement, AP, AP Central, and the acorn logo are registered trademarks of College Board Visit College Board on the web: collegeboard.org AP Central is the official online home for the AP Program: apcentral.collegeboard.org AP® Chemistry 2021 Scoring Guidelines Question 1: Long Answer (a) point For the correct expression: Ka = (b) 10 points [H 3O + ][HCOO − ] [HCOOH] For the correct calculated concentration of H3O+: I C E point → H O+ + HCOO– HCOOH + H2O ← 0.25 0 –x +x +x 0.25 – x x x x2 Let [H 3O ] = x, then 1.8 × 10 = (0.25 − x) x2 Assume x