.Chemical.Examples.GasSolubility_NIST

Information

Demonstration of CO2 and O2 dissolution in pure water as described by NIST Henry's law data at 25degC.

Recalculation from Henry's law constants ( https://webbook.nist.gov/cgi/inchi?ID=C124389&Mask=10#Solubility ):

CO2:

kH = 0.035 mol/(kg.bar) at 25degC

• pCO2 = 40 mmHg => dissolved CO2 .. 1.87 mmol/kg at 25degC

Other temperatures:

NIST constant ... 2400 K ( https://webbook.nist.gov/cgi/inchi?ID=C124389&Mask=10#Solubility )

0degC ... 0.035*exp(2400*(1/273.15 - 1/298.15) = 0.073 mol/(kg.bar)

• pCO2 = 40 mmHg => dissolved CO2 .. 3.9 mmol/kg at 0degC

37degC ... 0.035*exp(2400*(1/310.15 - 1/298.15) = 0.026 mol/(kg.bar)

• pCO2 = 40 mmHg => dissolved CO2 .. 1.4 mmol/kg at 37degC

O2:

kH = 0.0013 mol/(kg.bar) at 25degC

• pO2 = 95 mmHg (0.126656 bar) => dissolved O2 .. 0.165 mmol/kg at 25degC

Other temperatures:

NIST constant ... 1500 K ( https://webbook.nist.gov/cgi/cbook.cgi?ID=C7782447&Mask=10 )

0degC ... 0.0013*exp(1500*(1/273.15 - 1/298.15) = 0.0021 mol/(kg.bar)

• pO2 = 95 mmHg => dissolved O2 .. 0.26 mmol/kg at 0degC

37degC ... 0.0013*exp(1500*(1/273.15 - 1/298.15) = 0.0011 mol/(kg.bar)

• pO2 = 95 mmHg => dissolved O2 .. 0.14 mmol/kg at 37degC

Revisions

2015-2019

Marek Matejak, Charles University, Prague, Czech Republic