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Water Solubility (SW)


Water Solubility (SW) - "The solubility of a chemical in water may be defined as the maximum amount of the chemical that will dissolve in pure water at a specified temperature. Above this concentration, two phases will exist if the organic chemical is a solid or a liquid at the system temperature: a saturated aqueous solution and a solid or liquid organic phase. Aqueous concentrations are usually stated in terms of weight per weight (ppm, ppb, g/kg, etc.) or weight per volume (mg/L, moles/L, etc.)." - Lyman and others, 1990

Water Solubility (SW) - "Aqueous solubility is defined as the equilibrium distribution of a solute between water and solute phases at a given temperature and pressure. Because SW is the maximum solute concentration possible at equilibrium, it can function as a limiting factor in concentration-dependent processes." - Pontolillo and Eganhouse, 2001

Aqueous Solubility - "The extent to which a compound will dissolve in water. The log of solubility is generally inversely related to molecular weight." - U.S. Environmental Protection Agency, 2009

Related Definitions

Octanol-Water Partition Coefficient (KOW)

USGS Information on Water Solubility

Related Science Feature Articles

More Information on Water Solubility

  • The Kow Controversy, Renner, Rebecca, 2002, Environmental Science and Technology, v. 36, no. 21, p. 411A-413A.


Lyman, W.J., Reehl, W.F., and Rosenblatt, D.H., 1990, Handbook of chemical property estimation mathods--Environmental behavior of organic compounds: Washington, DC, American Chemical Society, 960 p.

Pontolillo, J., and Eganhouse, R.P., 2001, The search for reliable aqueous solubility (SW) and octanol-water partition coefficient (KOW) data for hydrophobic organic compounds--DDT and DDE as a case study: U.S. Geological Survey Water-Resources Investigations 01-4201, 51 p.

U.S. Environmental Protection Agency, 2009, Glossary of technical terms: U.S. Environmental Protection Agency, access date May 24, 2011.


Disclaimer: The definitions on this page are provided for information purposes only, and do not indicate endorment by the U.S. Geological Survey.

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