Dalton's
Law of Partial Pressure: used with a mixture of gases.
The total pressure in a container is the
sum of the partial pressures of all the gases in the container.
When a gas is collected by water
displacement in the lab, the collected sample will contain water
vapor. A calculation using Dalton's Law must be used to determine the
pressure of the dry gas (the gas with no water vapor). To do
this calculation, you will need the vapor pressure of water at the
collected temperature.
Portfolio Assignment
213: Scoring criteria
Work the following Dalton' Law
practice problems:
The total pressure in a closed
container of three mixed gases is 96.4 kPa. The partial pressure
of hydrogen in the mixture is 13.5 kPa and the partial pressure
of oxygen is 29.3 kPa. The third gas in the mixture is methane,
what is its partial pressure?
100 cm3 of hydrogen gas
are collected using water displacement in the lab. The
conditions at the time are 98.5 kPa and 24 oC. What
volume of dry hydrogen is collected?
325 cm3 of oxygen are
collected over water at 10 oC and 98 kPa. What will
be the volume of the dry gas at 101 kPa and 10 oC?
Information provided by: http://pc65.frontier.osrhe.edu