Title: precipitation
Long Title: IUPAC Gold Book - precipitation
DOI: 10.1351/goldbook.PT07627
Status: current

Definition
Sedimentation of a solid material (a precipitate) from a liquid solution in which the material is present in amounts greater than its solubility in the liquid.

Note
When precipitation occurs in sol-gel processing, sol particles have aggregated to a size where gravitational forces cause them to sink or float. Generally, aggregation arises from a change in the sol that reduces the interparticle repulsion.

Related Terms
- Sedimentation: https://goldbook.iupac.org/terms/view/S05534
- gel: https://goldbook.iupac.org/terms/view/G02600
- precipitation: https://goldbook.iupac.org/terms/view/P04795
- sol: https://goldbook.iupac.org/terms/view/S05727
- solubility: https://goldbook.iupac.org/terms/view/S05740

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 1824 (https://doi.org/10.1351/pac200779101801)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/PT07627/html
- json: https://goldbook.iupac.org/terms/view/PT07627/json
- xml: https://goldbook.iupac.org/terms/view/PT07627/xml

Citation: Citation: 'precipitation' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.PT07627
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Accessed: 2026-06-24T13:06:24+00:00