Daltons Law of Partial Pressures - Worked Problem

Daltons Law of Partial Pressures, or Daltons Law, states that the total pressure of a gas in a container is the sum of the partial pressures of the individual gases in the container. Here is a worked example problem showing how to use Daltons Law to calculate the pressure of a gas. Review Daltons Law Daltons Law of Partial Pressures is a gas law that can be stated: Ptotal P1 P2 P3 ... Pn where P1, P2, P3, Pn are the partial pressures of the individual gases in the mixture. Example Daltons Law Calculation The pressure of a mixture of nitrogen, carbon dioxide, and oxygen is 150 kPa. What is the partial pressure of oxygen if the partial pressures of the nitrogen and carbon dioxide are 100 kPA and 24 kPa, respectively? For this example, you can simply plug the numbers into the equation and solve for the unknown quantity. P Pnitrogen Pcarbon dioxide Poxygen150 kPa 100 kPa 24 kPa PoxygenPoxygen 150 kPa - 100 kPa - 24 kPaPoxygen 26 kPa Check your work. Its a good idea to add up the partial pressure to make sure the sum is the total pressure!