Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Densities and apparent molar volumes of HClO4(aq) and Yb(ClO4)3(aq) at elevated temperatures and pressures

Hakin, A. W.[Andrew W.], Lukacs, M. J.[Michael J.], Liu, J. L.[Jin Lian]
J. Chem. Thermodyn. 2004, 36, 9, 759-772
ABSTRACT
Relative densities have been measured for acidified aqueous solutions of ytterbium perchlorate {Yb(ClO4)3} at approximately T = (348:15; 373:15; 398:15; and 423:15) K and p = (10:0; 20:0; and 30:0? MPa over the concentration range 0:016246m2/ (mol.kg-1) 6 0.2531 using an optically coupled vibrating tube densimeter (OCVTD). Experimental apparent molar volumes have been calculated from the density measurements, and apparent molar volumes for the aqueous perchlorate salt have been calculated using Young_s rule. The application of Young_s rule requires apparent molar volumes for aqueous perchloric acid (HClO4) solutions over extended temperature and pressure ranges. These values were calculated from densities for aqueous HClO4 solutions that were measured using the OCVTD at the same temperatures and pressures as those used to investigate the density surface of the acidified aqueous Yb(ClO4)3 solutions. The temperature, pressure, and composition surfaces of the apparent molar volumes for Yb(ClO4)3(aq) and HClO4(aq) have been modelled using Pitzer ion-interaction equations. Apparent molar volumes at infinite dilution obtained from these models have been compared to those which can be calculated using the semi-empirical Helgeson, Kirkham, and Flowers equations of state. Values for the apparent molar volume at infinite dilution of the ytterbium trivalent cation have also been calculated using simple additivity principles.
Compounds
# Formula Name
1 ClHO4 perchloric acid
2 H2O water
3 Cl3O12Yb ytterbium perchlorate
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 2
  • 3
  • Mass density, kg/m3 ; Liquid
  • Molality, mol/kg - 3; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Liquid
  • VIBTUB:UFactor:2
  • 180
  • POMD
  • 1
  • 2
  • Mass density, kg/m3 ; Liquid
  • Temperature, K; Liquid
  • Pressure, kPa; Liquid
  • Molality, mol/kg - 1; Liquid
  • Liquid
  • VIBTUB:UFactor:2
  • 152