Also found in: Dictionary, Thesaurus, Medical, Legal, Financial, Acronyms, Wikipedia.
partial pressure[′pär·shəl ′presh·ər]
In a mixture of gases that occupies a certain volume, the partial pressure of each component gas is the pressure the gas would have if it alone occupied the same volume at the same temperature. Dalton’s law states that the total pressure of a mixture of gases is equal to the sum of the partial pressures of the mixture’s components. A gas’s partial pressure determines the course of the processes of diffusion, absorption, and solution of the gas, as well as of the distribution of the gas between two parts of a system where the parts are separated by a partition that is permeable to the gas.