Term: soot
https://doi.org/10.1351/goldbook.S05768

Definition:
A randomly formed particulate carbon material and may be coarse, fine and/or colloidal in proportions depending on its origin. Soot consists of variable quantities of carbonaceous and inorganic solids together with absorbed and occluded tars and resins.

Note: An unwanted by-product of incomplete combustion or @P04961@. Soot generated within flames consists essentially of aggregates of spheres of carbon. Soot found in domestic fireplace chimneys contains few aggregates but may contain substantial amounts of particulate fragments of @C01142@ or @C00974@. Soot from diesel engines consists essentially of aggregates together with tars and resins. For historical reasons, the term soot is sometimes incorrectly used for @C00824@. This misleading use should be avoided.

Related Terms:
1) pyrolysis (http://doi.org/10.1351/goldbook.P04961).
2) coke (http://doi.org/10.1351/goldbook.C01142).
3) colloidal (http://doi.org/10.1351/goldbook.C01172).
4) variable (http://doi.org/10.1351/goldbook.V06600).
5) char (http://doi.org/10.1351/goldbook.C00974).
6) carbon black (http://doi.org/10.1351/goldbook.C00824).
7) particulate carbon (http://doi.org/10.1351/goldbook.P04433).

Source: PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2215 (https://doi.org/10.1351/pac199062112167)

Citation: 'soot' 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.S05768

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