Term: efflorescence
https://doi.org/10.1351/goldbook.E01909

Definition:
The reverse of deliquescence: the drying of a salt solution when the vapour pressure of water in the saturated solution of a substance is greater than the partial pressure of water in the ambient air. Also refers to the loss of water of crystallization from a solid salt such as Na2CO3·10H2O.

Related Terms:
1) deliquescence (http://doi.org/10.1351/goldbook.D01582).
2) salt (http://doi.org/10.1351/goldbook.S05447).
3) saturated solution (http://doi.org/10.1351/goldbook.S05471).
4) partial pressure (http://doi.org/10.1351/goldbook.P04420).
5) crystallization (http://doi.org/10.1351/goldbook.C01434).

Source: PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2186 (https://doi.org/10.1351/pac199062112167)

Citation: 'efflorescence' 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.E01909

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