SDS Volume

Volume 62. Carbon Dioxide in Water and Aqueous Electrolyte Solutions, p None

Source Publication

He, S.; Morse, J. W.; Geochim. Cosmochim. Acta 1993, 57, 3533-54.

Conditions:

Room Temp: 273.15 - 363.15 $\pu{K}$
Pressure: 0.1032 $\pu{MPa}$
Molality (2): m₂/mol kg^-1 = 0.1 - 5.021 mol/kg

Compiler:

P. Scharlin

Methodology:

Either pure $\ce{CO2}$ gas or $\ce{CO2}-\ce{N2}$ mixtures were used in the experiments to maintain a constant P($\ce{CO2}$). The $\ce{CO2}-\ce{N2}$ mixtures were made by pumping predetermined amounts of $\ce{CO2}$ and $\ce{N2}$ into a gas tank and their composition was verified by gas chromatography.
$\ce{CO2}$ or $\ce{CO2}-\ce{N2}$ gas mixtures were equilibrated with the aqueous solutions in a series of stirred water-jacketed reaction vessels with condensers. The gas was pre-moistured by first passing it through distilled water at the temperature of experiment. Fine bubbles were obtained by using gas-dispersion tubes. The bubbling rate was 90-95 mL/min.
The mole fraction of $\ce{CO2}$ in the $\ce{CO2}-\ce{N2}$ mixture was determined using a Hewlett Packard (5790A) gas chromatograph.

Sample Information:

1. Commercial; purity 99.9%
2. Source not mentioned. Analytical reagent-grade which met ACS specifications. $\ce{MgCl2.6H2O}$ was weighed and dissolved in water. The concentration of $\ce{MgCl2}$ in solutions was determined by analyzing $\ce{Cl-}$ concentration via $\ce{AgNO3}$ titration in stock solutions.
3. 18 MΩ water obtained from a Milli-Q Super-Q water system.

Measurement Errors:

Ambient temperature: δT/K = ±0.1
Mass concentration (m/v) (1): δm₁/m₁ = ±0.012
δγ₁/γ₁ = ±0.04