Term: particle size
https://doi.org/10.1351/goldbook.P04430

Definition:
To describe the size of liquid or solid particles (aerosol) the average or equivalent diameter is used. For non-spherical particles collected in an impactor, for example, the aerodynamic diameter of a particle of arbitrary shape and density refers to the size of a spherical particle of unit density that would deposit on a given impactor surface.

Related Terms:
1) aerosol (http://doi.org/10.1351/goldbook.A00176).
2) equivalent diameter (http://doi.org/10.1351/goldbook.E02191).

Source: PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2205 (https://doi.org/10.1351/pac199062112167)

Citation: 'particle size' 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.P04430

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