1. Dalton’s Law of Partial Pressure

2. Dalton’s Law All gases behave pretty much the same.
Observe more than one gas in a sample.
If 2 or more gases are mixed in a container, each gas will exert a pressure  PARTIAL PRESSURE
Total pressure = sum of partial pressures

3. Dalton’s Law
PTOT = PA + PB + PC
Patm = PO2 + PN2 + PCO2 + PAr

4. Dalton’s Law
A sample relationship exists between the total pressure and individual partial pressures  MOLE FRACTION

5. Dalton’s Law Def: Mole Fraction = mols of one substance = X
total moles
(XA + XB +XC =1)
Partial Pressure = pressure exerted by only one gas in a mixture.
PA = nART/V or PA = XAPTOT

6. Dalton’s Law
Gases are often collected over water, hence the need for partial pressures.
PTOT = PGAS + PH20 VAPOR