When referring to the compilation of Henry's Law Constants, please cite
R. Sander: Compilation of Henry's law constants (version 4.0) for
water as solvent, Atmos. Chem. Phys., 15, 4399-4981 (2015),
Henry's law states that the amount of dissolved gas
is proportional to its partial pressure in the gas phase. The
proportionality factor is called the Henry's law constant. It was
formulated by the English chemist William Henry, who studied the topic
in the early 19th century.
A compilation of 17350 values of Henry's law constants for 4632 species,
collected from 689 references, has been published
by Sander (2015). Online access to the searchable
database is available here.
If you find errors or if you know of additional references that I could
include, please send me an email
Especially when you have published measurements of Henry's law's
constants, I would appreciate it very much if you send me a reprint!
What kind of data is included?
The list contains Henry's law constants for several organic and
inorganic species in water. The Henry's law constant is defined here as
the ratio of the aqueous-phase concentration of a chemical to its
equilibrium partial pressure in the gas phase.
What kind of data is NOT included?
Henry's law refers to small concentrations (lim c→0). Maximum
solubilities are not included. Solubility products, i.e. products of ion
concentrations are not included either.
Henry's law constants for solvents other than water are not included.
Values obtained under high pressures (p >> 1000 hPa) and
temperatures (T > 373 K) are not included.
Pressure or fugacity?
The official IUPAC definition of Henry's law constants uses fugacity to
describe the gas-phase composition. In my compilation, I use pressure.
In other words, I am assuming a fugacity coefficient of 1. I think that
this simplification is acceptable in environmental science where the
partial pressures of trace gases are small. As mentioned above, values
obtained under high pressures are not included in my list.
Older (obsolete) versions of the compilation are also still available:
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Search Henry's Law Database
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Convert Henry's Law Constants
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