AP Chemistry · Reference

AP Chemistry formula sheet every equation by topic.

Here is the full AP Chemistry formula sheet, also called the equation sheet, organized by topic from atomic structure to electrochemistry. The College Board gives you this reference packet — plus a periodic table — for both sections on exam day, so the goal is to know what each formula does, not to memorize it.

Updated June 2026Part of AP Chemistry Review

Is the equation sheet provided on the AP Chemistry exam?

Yes. The official AP Chemistry reference packet of equations and constants, along with a periodic table, is provided for both the multiple-choice and free-response sections. You are not expected to memorize the formulas — the exam tests whether you can pick the right one and apply it.

One catch worth remembering: you get the equation sheet on both sections, but a calculator only on the free response. So on the multiple choice you still need to reason through the numbers. The version below is grouped by topic so each formula connects to the unit it belongs to.

The AP Chemistry formula sheet, by topic

Every relationship you are handed on test day, with a plain-language note on when to use it.

Atomic structure & light

E = hν

Energy of a photon.

c = λν

Wavelength and frequency of light.

Gases & solutions

PV = nRT

Ideal gas law.

P_A = X_A · P_total

Partial pressure from mole fraction.

M = n/V

Molarity: moles of solute per liter.

A = εbc

Beer’s law for absorbance.

Kinetics

rate = k[A]^m[B]ⁿ

Rate law.

[A] = [A]₀ − kt

Zero-order integrated rate law.

ln[A] = ln[A]₀ − kt

First-order integrated rate law.

1/[A] = 1/[A]₀ + kt

Second-order integrated rate law.

Equilibrium, acids & bases

K = [products]/[reactants]

Equilibrium constant (each raised to its coefficient).

K_w = [H⁺][OH⁻] = 1.0 × 10⁻¹⁴

Autoionization of water at 25°C.

pH = −log[H⁺], pH + pOH = 14

pH, pOH, and their sum.

K_a · K_b = K_w

For a conjugate acid–base pair.

pH = pK_a + log([A⁻]/[HA])

Henderson–Hasselbalch (buffers).

Thermodynamics

q = mcΔT

Heat exchanged (calorimetry).

ΔH° = ΣΔH_f°(products) − ΣΔH_f°(reactants)

Standard enthalpy of reaction.

ΔG° = ΔH° − TΔS°

Gibbs free energy.

ΔG° = −RT·ln K

Free energy and the equilibrium constant.

Electrochemistry

ΔG° = −nFE°_cell

Free energy from cell potential.

q = I·t

Charge from current and time.

Constants provided on the sheet

R = 8.314 J/(mol·K) = 0.08206 L·atm/(mol·K)

The gas constant, in two useful forms.

F = 96,485 C/mol

Faraday’s constant.

N_A = 6.022 × 10²³ mol⁻¹

Avogadro’s number.

h = 6.626 × 10⁻³⁴ J·s

Planck’s constant.

c = 3.00 × 10⁸ m/s

Speed of light.

The periodic table is provided too

Along with the equations and constants, you get a full periodic table showing each element’s atomic number, symbol, and atomic mass. You can pull the official equations-and-constants packet and periodic table from the College Board’s AP Chemistry exam page to practice with the exact layout you will see on test day.

How to use the equation sheet

Treat the sheet as a map, not a crutch. In your studying, practice naming which equation fits a problem and why, because that judgment is what the questions test. Knowing the layout also saves time, especially on the no-calculator multiple choice.

For a faster, concept-first version that pairs each unit with its key idea and the mistake to avoid, use our AP Chemistry cheat sheet, and the score calculator turns a practice raw score into a 1–5.

Frequently asked questions

Quick answers — written by humans, not a chatbot.

Is the AP Chemistry equation sheet provided on the exam?

Yes — the equations, constants, and a periodic table are provided for both sections, so you do not memorize the formulas.

Is a calculator allowed with the AP Chemistry equation sheet?

You get the equation sheet on both sections, but a calculator only on the free response, not the multiple choice.

Is a periodic table provided on the AP Chemistry exam?

Yes, a full periodic table is included along with the equations and constants packet.

What do I still need to memorize for AP Chemistry?

Not the formulas, but the concepts — which relationship applies, what each symbol means, polyatomic ions, and how to justify your reasoning.

What is the difference between the equation sheet and a cheat sheet?

The equation sheet is the official packet you are handed. A cheat sheet is a study tool that adds the key idea and common mistake for each unit — see our cheat sheet.