Dalton's Law of Partial Pressure states that in a gas mixture, each gas exerts its own independent pressure, called its partial pressure, and the total pressure is the sum of the partial pressures of the individual gases. The partial pressure of a gas depends on the number of moles of gas, the volume of the container, and temperature, but not on the identity of the other gases present. Dalton's Law allows calculation of the partial pressure of each gas in a mixture from the total pressure and mole fractions of the gases.

1. Dalton’s Law of Partial Pressure

2. Each gas in a mixture independently of the other gases present.The total pressure of a mixture equals the sum of the pressures in the mixture.Ptotal= P1+ P2+ P3+… PnDalton’s Law

3. The pressure exerted by a single gas is the partial pressure.This depends on the number of moles of the gas, the size of the container, and the temperature of the mixture.It does NOT depend on the type of gas.Dalton’s Law continued

4. At a given temperature and pressure, the partial pressure of one mol of any gas is the same.When a gas is collected over water, it will be a mixture of the gas and water vapor.Partial pressure of the water vapor has a fixed value at a given temperature.Partial Pressure