What is 'partial pressure' in a gas mixture?

Partial pressure refers to the pressure exerted by an individual gas within a mixture of gases. This concept is fundamental in understanding gas behavior, particularly in applications of Dalton's Law of Partial Pressures, which states that the total pressure exerted by a mixture of non-reacting gases is equal to the sum of the partial pressures of each gas.

In a mixture, each gas contributes to the total pressure in proportion to its amount and temperature, and the partial pressure of a specific gas can be determined by its mole fraction in the mixture multiplied by the total pressure of the gas mixture. This concept is essential for calculations involving gas mixtures, such as in respiratory physiology, industrial applications, and various chemical reactions, where understanding how different gases interact and contribute to the overall pressure is crucial.