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A first-order reaction has a rate constant of 0.025 s⁻¹. How long will it take for [A] to decrease to 50% of its initial value?
Accuracy
87%
Streak
7 days
Everything you need to study. Nothing you don't.
All 9 units, broken down by topic. If your teacher just finished kinetics, drill kinetics.
Toggle MCQ and FRQ. The exam asks both, so you should practice both.
Why the right answer is right — and why the trap answer was the trap.
Your weak topics, color-coded by unit. Obvious where to spend your study hours.
College Board aligned, exam-focused content.
Explore the structure of atoms, electron configuration, and the periodic table. Understand how atomic properties connect to chemical behavior.
Study chemical bonding, Lewis structures, resonance, formal charge, molecular geometry, polarity, and the structure of ionic and metallic solids.
Study intermolecular forces, solids, gases, solutions, solubility, spectroscopy, and Beer-Lambert law.
Translate among symbolic, particulate, and quantitative views of chemical change. Build skill with reaction evidence, net ionic equations, stoichiometry, titrations, acid-base chemistry, and redox.
Study reaction rates, rate laws, mechanisms, collision theory, energy profiles, and catalysis.
Study energy flow, calorimetry, phase changes, reaction enthalpy, bond enthalpy, enthalpy of formation, and Hess's law.
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Class of 2024 • AP Chem Score: 5
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Class of 2024 • AP Chem Score: 5
“The weak areas tracker showed me exactly what to study. I focused my last two weeks on acids & bases and kinetics and it made all the difference.”
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Class of 2023 • AP Chem Score: 4
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