Skip to main content
We’re so back. See what’s new for the 2026-2027 school year →

AP Chemistry MCQs

Pep mascot

Content Filters

Question Types

Tools

Export assessment:print

Not sure where to begin?

  • Recommended study guides

  • Answer 5 questions to see which guides will help you the most

Practice Settings

AP Chemistry practice questions by unit

Fiveable has 27,339 AP Chemistry multiple-choice practice questions across 9 units, plus 450 stimulus-based question sets built around a source. Practice one unit or topic at a time.

  • Unit 1 – Atomic Structure & Properties: 1,893 multiple-choice questions, 37 stimulus sets
  • Unit 2 – Compound Structure and Properties: 1,506 multiple-choice questions, 37 stimulus sets
  • Unit 3 – Properties of Substances and Mixtures: 2,810 multiple-choice questions, 70 stimulus sets
  • Unit 4 – Chemical Reactions: 2,369 multiple-choice questions, 39 stimulus sets
  • Unit 5 – Kinetics: 3,494 multiple-choice questions, 54 stimulus sets
  • Unit 6 – Thermochemistry: 3,306 multiple-choice questions, 45 stimulus sets
  • Unit 7 – Equilibrium: 4,074 multiple-choice questions, 44 stimulus sets
  • Unit 8 – Acids & Bases: 3,993 multiple-choice questions, 62 stimulus sets
  • Unit 9 – Thermodynamics and Electrochemistry: 3,894 multiple-choice questions, 62 stimulus sets

Sample AP Chemistry practice question

A researcher plots the standard Gibbs free energy change (ΔG°) on the y-axis versus temperature (T) on the x-axis for a chemical reaction. The resulting line has a negative slope and a positive y-intercept. Based on the linear relationship ΔG° = ΔH° − TΔS°, which statement correctly identifies the signs of the enthalpy and entropy changes indicated by the graph?

The enthalpy change is positive and the entropy change is positive.

Correct answer

The enthalpy change is positive and the entropy change is negative.

The enthalpy change is negative and the entropy change is positive.

The enthalpy change is negative and the entropy change is negative.

Explanation

Connecting the linear equation y = mx + b to the thermodynamic function shows that the y-intercept corresponds to ΔH° and the slope corresponds to −ΔS°. A positive intercept indicates ΔH° > 0, and a negative slope indicates −ΔS° < 0, meaning ΔS° must be positive.

More AP Chemistry practice