AP Chemistry Reference

Equations & Constants

Every formula on the official exam reference sheet, each wired to a live calculator. Click any equation to solve it. The official sheet can be found here.

Unit symbols

gramg

molemol

literL

meterm

seconds

hertzHz

atmosphereatm

millimeter of mercurymm Hg

degree Celsius°C

kelvinK

jouleJ

voltV

coulombC

ampereA

Unit conversions

1 hertz = 1 s^{- 1}

1 atm = 760 mm Hg = 760 torr

K =^{\circ} C + 273.15

1 volt = \frac{1 joule}{1 coulomb}

1 ampere = \frac{1 coulomb}{1 second}

Metric prefixes

FactorPrefixSym

$1 0^{9}$ giga $G$

$1 0^{6}$ mega $M$

$1 0^{3}$ kilo $k$

$1 0^{- 2}$ centi $c$

$1 0^{- 3}$ milli $m$

$1 0^{- 6}$ micro $μ$

$1 0^{- 9}$ nano $n$

$1 0^{- 12}$ pico $p$

Atomic Structure

Symbols

E

energy

ν

frequency

λ

wavelength

F

force

q

charge

r

separation

Constants

Planck’s constant, h

6.626 \times 1 0^{- 34} J s

Speed of light, c

2.998 \times 1 0^{8} m s^{- 1}

Avogadro’s number

6.022 \times 1 0^{23} mol^{- 1}

Gases, Liquids, And Solutions

Symbols

P

pressure

V

volume

T

temperature

n

number of moles

X

mole fraction

m

mass

M

molar mass

D

density

K E

kinetic energy

v

velocity

M

molarity

A

absorbance

ε

molar absorptivity

b

path length

c

concentration

Constants

Gas constant, R

8.314 J mol^{- 1} K^{- 1} = 0.08206 L atm mol^{- 1} K^{- 1}

STP

273.15 K and 1.0 atm

Ideal gas at STP

22.4 L mol^{- 1}

Kinetics

Symbols

k

rate constant

t

time

t_{1/2}

half-life

Equilibrium

Equilibrium Constants

$K_{c}$ (molar concentrations)

$K_{p}$ (gas pressures)

$K_{w}$ (water)

$K_{a}$ (acid)

$K_{b}$ (base)

Thermodynamics / Electrochemistry

Symbols

q

heat

m

mass

c

specific heat capacity

T

temperature

S^{\circ}

standard entropy

H^{\circ}

standard enthalpy

G^{\circ}

standard Gibbs free energy

R

gas constant

K

equilibrium constant

n

number of moles of electrons

E^{\circ}

standard potential

I

current (amperes)

q

charge (coulombs)

t

time (seconds)

Q

reaction quotient

Constants

Faraday’s constant, F

96, 485 C / 1 mol e^{-}