SDS Volume (2816)
Volume 62. Carbon Dioxide in Water and Aqueous Electrolyte Solutions, p None
Original Measurements
He, S.; Morse, J. W.; Geochim. Cosmochim. Acta 1993, 57, 3533-54.
Variables:
Room Temp:
273.15 - 363.15
$\pu{K}$
Pressure:
0.1032
$\pu{MPa}$
Molality (2):
m2/mol kg-1 = 0.01 - 3.00
mol/kg
Prepared by:
Method/Apparatus/Procedure:
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.
Source and Purity of Materials:
- Commercial; purity 99.9%
- Hydrochloric acid solutions were prepared by diluting concentrated $\ce{HCl}$ and standardizing the solution by titration. $\ce{HCl}$ was analytical reagent-grade which met ACS specifications.
- 18 MΩ water obtained from a Milli-Q Super-Q water system.
Estimated Errors:
Ambient temperature: δT/K = ±0.1
Mass concentration (m/v) (1): δm1/m1 = ±0.012
δγ1/γ1 = ±0.04
Components:
- Carbon dioxide, $\ce{ CO2 }$; [124-38-9] NIST WebBook
- Hydrogen chloride, $\ce{ HCl }$; [7647-01-0] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
| $T$ ($\pu{K}$) | m1 (mol/kg) | m2 (mol/kg) | ρ (g/cm3) | γ |
|---|---|---|---|---|
| 273.15 | 0.0749 | 0.01 | 1.0011 | 1.01 |
| 273.15 | 0.0742 | 0.10 | 1.0027 | 1.02 |
| 273.15 | 0.0707 | 1.00 | 1.0189 | 1.07 |
| 273.15 | 0.0687 | 2.00 | 1.0358 | 1.10 |
| 273.15 | 0.0666 | 3.00 | 1.0520 | 1.13 |
| 298.15 | 0.0319 | 0.01 | 0.9977 | 1.01 |
| 298.15 | 0.0318 | 0.10 | 0.9992 | 1.01 |
| 298.15 | 0.0309 | 1.00 | 1.0144 | 1.04 |
| 298.15 | 0.0294 | 2.00 | 1.0303 | 1.09 |
| 298.15 | 0.0286 | 3.00 | 1.0452 | 1.12 |
| 323.15 | 0.0166 | 0.01 | 0.9888 | 1.00 |
| 323.15 | 0.0166 | 0.10 | 0.9903 | 1.01 |
| 323.15 | 0.0163 | 1.00 | 1.0050 | 1.02 |
| 323.15 | 0.0160 | 2.00 | 1.0204 | 1.04 |
| 323.15 | 0.0156 | 3.00 | 1.0347 | 1.06 |
| 348.15 | 8.1 x 10-3 | 0.01 | 0.9760 | 1.00 |
| 348.15 | 8.0 x 10-3 | 0.10 | 0.9775 | 1.01 |
| 348.15 | 7.9 x 10-3 | 1.00 | 0.9924 | 1.02 |
| 348.15 | 7.9 x 10-3 | 2.00 | 1.0079 | 1.03 |
| 348.15 | 7.7 x 10-3 | 3.00 | 1.0244 | 1.05 |
| 363.15 | 3.5 x 10-3 | 0.01 | 0.9656 | 1.00 |
| 363.15 | 3.4 x 10-3 | 0.10 | 0.9724 | 1.00 |
| 363.15 | 3.4 x 10-3 | 1.00 | 0.9896 | 1.01 |
| 363.15 | 3.4 x 10-3 | 2.00 | 0.9975 | 1.02 |
| 363.15 | 3.3 x 10-3 | 3.00 | 1.0214 | 1.03 |
(d) p1 = partial pressure of CO2
(e) m1 = molality of CO2
(f) γ1 = activity coefficient of CO2
(a) Calculated by the compiler.
(b) m2 = molality of HCl
(c) p = density of solvent
