Definition. The partial pressure of a given gas is defined as the pressure exerted by that gas alone. For example, consider the gaseous mixture of oxygen, nitrogen, carbon dioxide, and water vapor, the typical mixture found in alveolar gas.
From Wikipedia, the free encyclopedia. Philadelphia County is a county located in the commonwealth of Pennsylvania. At the 2010 census, the population was 1,526,006, making it the most populous county in the state, despite being the second smallest county in the state by land area.
For the present borough in Allegheny County, see Whitehall, Allegheny County, Pennsylvania. Whitehall Borough is a defunct borough that was located in Philadelphia County, Pennsylvania. The borough ceased to exist when it was incorporated into the City of Philadelphia on the passage of the Act of Consolidation, 1854. The area takes its name from White Hall, a grand mansion built there by Jesse Waln.