Dalton's Law of Partial Pressure

The next important law concerning gases is Dalton's Law of Partial Pressure. The formula and mathematical equation for Dalton's Law of Partial Pressure is given below along with definition of partial pressure.

What is Dalton's Law?

In a mixture of gases, the total pressure is equal to the sum of the partial pressures of the individual gases. Dalton's Law of Partial Pressure can be shown in the mathematical equation and formula below.

For three gases, A, B and C in a mixture, Dalton's Law of Partial Pressure gives:

where:

• P is the total pressure of the mixture
• P_A is the partial pressure of A
• P_B is the partial pressure of B
• P_C is the partial pressure of C

What is the definition of Partial Pressure?

The partial pressure of a gas is the pressure that the gas would exert if it alone occupied the whole volume of the mixture at the same temperature. For A, the partial pressure: