mole fraction
the number of moles of a component divided by the total number of moles
mole fraction = partial pressure/total pressure
partial pressure
the pressure due to any one component of an ideal gas mixture
the molecules of an ideal gas do not interact; they act independently of one another
partial pressure = n(RT/V)
the sum of all partial pressures in an ideal gas mixture is the total pressure
total pressure
the sum of all partial pressures in an ideal gas mixture
P total = n(RT/V) + n(RT/V) + n(RT/V)
= (n+n+n)(RT/V)
= ( RT/V)
STP (conditions)
T= 0�C, 273 K
P = 1.00 atm, 760 torr
V = 22.4 L
R = (constant)
Ideal Gas Constant
R = 0.08206 L?atm/mol?K
Atmosphere
unit of pressure
1 atm = 760 mmHg = 760 torr = 14.7 psi
Avogadro's Law
The volume of a gas increases in direct proportion to the amount of gas present; when temperature and pressure are constant.
V?/n? = RT/P = V?/n?
Boyle's Law
Pressure and volume are inversely proportional. If the volume of a gas is decreased, the number of particles present generate more collisions with the walls, thereby increasing pressure. The amount and temperature are kept constant.
P?V?=P?V?
Charle's Law
Temperature and volume have a linear relationship; as temperature increases, volume increases.
Increased temperatures increase the amount of movement between particles. Frequency of collisions increases, and the amount of force on the container increases.
molar volume
volume occupied by one mole of a substance
density of a gas
density = mass/volume
d = n/V = P/RT
d = P(MW) / RT