AP Chemistry Equations & Constants
ADVANCEDPLACEMENT
PLACEMENTCHEMISTRY
CHEMISTRYEQUATIONS
EQUATIONSAND
ANDCONSTANTS
CONSTANTS
ADVANCED
Throughoutthe
thetest
testthe
thefollowing
followingsymbols
symbolshave
havethe
thedefinitions
definitionsspecified
specifiedunless
unlessotherwise
otherwisenoted.
noted.
Throughout
L,mL
mL
L,
gg
nm
nm
atm
atm
==
==
==
==
liter(s),milliliter(s)
milliliter(s)
liter(s),
gram(s)
gram(s)
nanometer(s)
nanometer(s)
atmosphere(s)
atmosphere(s)
ATOMICSTRUCTURE
STRUCTURE
ATOMIC
EE == hhνν
λν
cc == λν
mmHg
Hg
mm
kJ
J,J,kJ
VV
mol
mol
==
==
==
==
millimetersof
ofmercury
mercury
millimeters
joule(s),kilojoule(s)
kilojoule(s)
joule(s),
volt(s)
volt(s)
mole(s)
mole(s)
energy
EE == energy
frequency
νν == frequency
wavelength
λλ == wavelength
−34
Planck’sconstant,
constant,hh == 6.626
6.626××10
10−34
Planck’s
JJss
−1
mss−1
Speedof
oflight,
light,cc == 2.998
2.998××10
1088m
Speed
−1
Avogadro’snumber
number == 6.022
6.022××10
102323mol
mol−1
Avogadro’s
−19
Electroncharge,
charge,ee == −1.602
−1.602××10
10−19
coulomb
Electron
coulomb
EQUILIBRIUM
EQUILIBRIUM
[C]cc [D]dd
[A] [B]
[B]
[A]
EquilibriumConstants
Constants
Equilibrium
((PPCC))cc((PPDD))dd
(molarconcentrations)
concentrations)
KKcc (molar
(gaspressures)
pressures)
KKpp (gas
[C] [D]
R ccCC++ddD
where aaAA++bbBB R
D
,,where
KKcc ==
aa bb
KKpp ==
((PPAA))aa((PPBB))bb
[H++ ][A-- ]
KKaa == [H ][A ]
[HA]
[HA]
KKbb ==
[OH--][HB
][HB++]]
[OH
[B]
[B]
(weakacid)
acid)
KKaa (weak
(weakbase)
base)
KKbb (weak
(water)
KKww (water)
−14
[H++][OH
][OH−−]] == 1.0
1.0 ××10
10−14
25°C
atat25°C
KKww == [H
== KKaa××KKbb
pOH==−log[OH
−log[OH−−]]
pH == −log[H
−log[H++]],, pOH
pH
14 == pH
pH++pOH
pOH
14
[A--]]
pH == pK
pKaa++log
log[A
pH
[HA]
[HA]
pKaa==−logK
−logKaa,, pK
pKbb ==−logK
−logKbb
pK
KINETICS
KINETICS
ln[A]t t−−ln[A]
ln[A]00 == −−ktkt
ln[A]
11 -- 11
[[AA]]t t [[AA]]00
== ktkt
0.693
0.693
tt½
½ == kk
rateconstant
constant
kk == rate
time
tt ==time
tt½
half-life
½ == half-life
GASES, LIQUIDS, AND SOLUTIONS
PV = nRT
PA = Ptotal × XA, where XA =
moles A
total moles
Ptotal = PA + PB + PC + . . .
n= m
M
K = °C + 273
D= m
V
KE per molecule = 1 mv 2
2
Molarity, M = moles of solute per liter of solution
A = abc
THERMOCHEMISTRY/ ELECTROCHEMISTRY
q = mcDT
=
DSD Â SD products - Â SD reactants
=
DH D Â DHfD products - Â DH fD reactants
=
DGD Â DGfD products - Â DGfD reactants
G D DH D - T D S D
D=
= - RT ln K
= - n F ED
I
q
t
P
V
T
n
m
M
D
KE
Ã
A
a
b
c
=
=
=
=
=
=
=
=
=
=
=
=
=
pressure
volume
temperature
number of moles
mass
molar mass
density
kinetic energy
velocity
absorbance
molar absorptivity
path length
concentration
Gas constant, R = 8.314 J mol -1 K -1
= 0.08206 L atm mol -1 K -1
= 62.36 L torr mol -1 K -1
1 atm = 760 mm Hg
= 760 torr
STP = 0.00 D C and 1.000 atm
q
m
c
T
SD
=
=
=
=
heat
mass
specific heat capacity
temperature
= standard entropy
D
H = standard enthalpy
GD = standard free energy
n = number of moles
E D = standard reduction potential
I = current (amperes)
q = charge (coulombs)
t = time (seconds)
Faraday’s constant, F = 96,485 coulombs per mole
of electrons
1 joule
1volt =
1 coulomb