Term: pressure, p
https://doi.org/10.1351/goldbook.P04819

Definition:
Normal force acting on a surface divided by the area of that surface. For a mixture of gases the contribution by each constituent is called the partial pressure p i = x i p, where x i is the amount fraction x (y for gaseous mixtures) of the ith constituent and p is the total pressure.

Related Terms:
1) constituent (http://doi.org/10.1351/goldbook.C01281).
2) partial pressure (http://doi.org/10.1351/goldbook.P04420).
3) amount fraction <em>x</em> (<em>y</em> for gaseous mixtures) (http://doi.org/10.1351/goldbook.A00296).

Source: Green Book, 2nd ed., p. 12 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Citation: 'pressure, p' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.P04819

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