Dalton's Law Calculation

Dalton's Law of Partial Pressures, or Dalton's 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 Dalton's Law to calculate the pressure of a gas.

Dalton's Law

Dalton's Law of Partial Pressures is a gas law that can be stated:

P_total = P₁ + P₂ + P₃ + ... P_n

where P₁, P₂, P₃, P_n are the partial pressures of the individual gases in the mixture.

Example Dalton's 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?

P = P_nitrogen + P_{carbon dioxide} + P_oxygen

150 kPa = 100 kPa + 24 kPa + P_oxygen

P_oxygen = 150 kPa - 100 kPa - 24 kPa

P_oxygen = 26 kPa