P= pressure
V= volume
T= absolute temperature
n= number of moles
D = density
m= mass
v= velocity
urms= root mean square velocity
KE= kinetic energy
r= rate of effusion
M = molar mass
π= osmotic pressure
i= van’t Hoff factor
kf= molal freezing-point depression constant
kb= molal boiling-point elevation constant
Q= reaction quotient
Gas constant: R= 8.31 joules/(mole ⋅K)
= 0.0821 (liter ⋅atm)/(mole ⋅K)
= 8.31 (volt ⋅coulomb)/(mole ⋅K)
Boltzmann’s constant: k= 1.38 × 10 –23joule/K
kffor H 2 O = 1.86 (K ⋅kg)/mole
kbfor H 2 O = 0.512 (K ⋅kg)/mole
STP = 273 K and 1.000 atmospheres
Part IV: AP Chemistry Practice Test