Avogadro’s Law
We Know That 1 Mole of Gas = __________ L
Avogadro looked at the relationship between volume
and the number of moles of gas
He found:
For a gas at constant temperature and pressure, the
volume is directly proportional to number of moles of
gas.
V1 / n1 = V 2 / n2
Example:
Sample 1 of oxygen gas is 10 L and 0.50 mol.
Sample 2 of oxygen gas occupies 40 L, how many
moles of oxygen are in Sample 2?
Ideal Gas Law
If we combine Boyle’s, Charles’, and
Avogadro’s Laws, we can then see how
pressure, volume, temperature, and moles all
interrelate.
PV = nRT
P = Pressure (atm)
V = Volume (L)
n = number of moles (mol)
R = Universal Gas Constant = .08206
(atm*L/mol*K)
T = Temperature (K)
Example:
A sample of neon has a volume of 9.4 L at a
temperature of 0˚C and a pressure of 2 atm.
Calculate the number of moles of neon in this
sample.