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Chemistry
AP Annual Conference Submission
Greg Dodd
AP Chemistry Consultant
George Washington High School
Big Idea 3 and Learning Objective 6.7 specify that students should understand equilibrium and be able to determine a K value for either a large or a small K. Question #3 (.45/4) from the 2016 AP Chemistry Exam and Question #3 (2.95/10) from the 2017 Exam indicate students still have serious misconceptions. Seventy-three % of the students received a zero or had no response to the 2016 equilibrium question. Exam results showed failure to correct for dilution and to realize the consequences of a Large K, assuming x is negligible, confusing moles with concentration, and concluding Q = K. Students are most familiar with equilibrium problems/experiments with a small K value (usually less than 1), but the 2016 AP question dealt with a large K value. This “hands on” inquiry is an activity designed to help overcome student misconceptions of equilibrium while supporting Learning Objective 6.7; and Science Practices 1-7. Handouts will be provided and time allotted for questions.