Term: aerosol
https://doi.org/10.1351/goldbook.A00176

Definition:
sol in which the dispersed phase is a solid, a liquid or a mixture of both and the continuous phase is a gas (usually air).

Notes:
0) Owing to their size, the particles of the dispersed phase have a comparatively small @S05631@ and hence exhibit some degree of stability in the earth's gravitational field.
1) An aerosol can be characterized by its chemical composition, its @R05092@ (if any), the particle size distribution, the electrical charge and the optical properties.
2) Modified from previous definition, within which particles with equivalent diameters usually between 0.01 and 100 µm are specified. This extends beyond the size range specified for a @C01172@ system. To avoid confusion the definition proposed here is recommended.

Related Terms:
1) sol (http://doi.org/10.1351/goldbook.S05727).
2) settling velocity (http://doi.org/10.1351/goldbook.S05631).
3) radioactivity (http://doi.org/10.1351/goldbook.R05092).
4) colloidal (http://doi.org/10.1351/goldbook.C01172).

Source: PAC, 2007, 79, 1801. 'Definitions of terms relating to the structure and processing of sols, gels, networks, and inorganic-organic hybrid materials (IUPAC Recommendations 2007)' on page 1805 (https://doi.org/10.1351/pac200779101801)

Citation: 'aerosol' 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.A00176

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