Model III Data

The System

The sources of data used to determine mixture parameters W, Q and U in the activity coefficient equations for this ternary system are listed in Table 6 of Clegg et al. (1998b). Fits of the model are described in section 3.8 of that paper. The following types of data were used:

Solubilities of the solids Na2SO4.10H2O(s), Na2SO4(s), Na3H(SO4)2(s), NaHSO4.H2O(s), NaHSO4(s), and NaH3(SO4)2.H2O(s) in the ternary solutions.
Osmotic coefficients from isopiestic vapour pressure measurements.
Activity coefficients of H2SO4 from electromotive force measurements.
Osmotic coefficients from electrodynamic balance measurements.

References: S. L. Clegg, P. Brimblecombe and A. S. Wexler (1998b) J. Phys. Chem. A 102, 2155-2171.

Weights

The values listed in the tables below are based upon those used in the fits of the model. However, they have been normalised for each type of measurement so that the maximum weight for a data point in each table is always unity. Points given zero weight are those which either appear to be in error, or are used for comparison only (and were not fitted). Points with a weight of "-" are outside the temperature or concentration limits of the current model, and have not been assessed for accuracy.

The Data

The experimental data used to fit the activity coefficient model are listed in the tables below. Notes at the end of each one define the tabulated quantities, and identify the sources of the measurements.

(1) Solubilities of Solid Phases

    mH2SO4    mNa2SO4      t       solid    ref.      weight     
    2.779     4.265       16.70      1     a(756)       -      
    2.779     4.265       16.70      4     a(756)       -      
    2.779     4.265       16.70      7     a(756)       -      
    0.889     2.727       25.00      1     a(756)      0.0     
    2.299     3.122       25.00      1     a(756)      0.0     
    8.879     1.626       25.00      5     a(756)      0.04    
   11.048     1.053       25.00      5     a(756)      0.04    
   21.606     1.049       25.00      8     a(756)      0.0     
   24.286     1.078       25.00      8     a(756)      0.0     
    7.849     0.203      -45.00      2     a(758)       -      
    7.849     0.203      -45.00      1     a(758)       -      
    7.849     0.203      -30.00      2     a(758)       -      
    6.242     0.267      -30.00      2     a(758)       -      
    3.898     0.311      -30.00      2     a(758)       -      
    4.566     0.315      -24.00      0     a(758)       -      
    6.207     0.918      -24.00      0     a(758)       -      
    6.207     0.918      -24.00      2     a(758)       -      
    6.207     0.918      -24.00      1     a(758)       -      
    7.769     1.006      -21.00      5     a(758)       -      
    7.769     1.006      -21.00      5     a(758)       -      
    3.399     0.290      -17.00      0     a(758)       -      
    5.098     1.173      -11.00      1     a(758)       -      
    1.912     0.440      -10.00      1     a(758)       -      
    1.912     0.440      -10.00      0     a(758)       -      
    1.508     0.250       -9.00      0     a(758)       -      
    3.399     1.043       -7.00      1     a(758)       -      
    8.997     0.552       -6.00      2     a(758)       -      
    5.566     1.090       -3.00      7     a(758)       -      
    1.410     0.915       -3.00      1     a(758)       -      
    4.856     1.980       -3.00      6     a(758)       -      
    3.972     2.461       -3.00      6     a(758)       -      
    0.787     0.482        0.00      1     a(758)       -      
    1.944     0.719        0.00      1     a(758)       -      
    3.074     1.191        0.00      1     a(758)       -      
    3.452     1.591        0.00      1     a(758)       -      
    3.794     2.417        0.00      1     a(758)       -      
    3.956     2.921        0.00      1     a(758)       -      
    4.534     4.015        0.00      1     a(758)       -      
    4.669     3.962        0.00      2     a(758)       -      
    4.861     3.701        0.00      2     a(758)       -      
    4.904     3.607        0.00      2     a(758)       -      
    5.217     3.170        0.00      7     a(758)       -      
    5.757     2.529        0.00      7     a(758)       -      
    5.935     2.193        0.00      5     a(758)       -      
    6.251     1.830        0.00      5     a(758)       -      
    6.272     1.701        0.00      5     a(758)       -      
    6.322     1.214        0.00      5     a(758)       -      
    6.882     0.978        0.00      5     a(758)       -      
    8.378     0.532        0.00      5     a(758)       -      
   14.516     0.368        0.00      5     a(758)       -      
   15.222     0.428        0.00      5     a(758)       -      
   16.442     0.528        0.00      5     a(758)       -      
   17.533     0.602        0.00      5     a(758)       -      
   18.796     0.713        0.00      6     a(758)       -      
   18.983     0.701        0.00      6     a(758)       -      
   23.679     0.000        0.00      6     a(758)       -      
    1.154     1.270        5.00      1     a(758)       -      
    2.564     3.024        5.00      1     a(758)       -      
    3.406     4.689        5.00      1     a(758)       -      
    3.406     4.689        5.00      4     a(758)       -      
    5.190     3.683        5.00      2     a(758)       -      
    6.829     2.278        5.00      2     a(758)       -      
    9.522     0.709        5.00      2     a(758)       -      
    9.522     0.709        5.00      5     a(758)       -      
   10.497     0.625        5.00      5     a(758)       -      
   16.086     0.748        5.00      6     a(758)       -      
   25.554     0.237        5.00      6     a(758)       -      
   46.000     0.074        5.00      9     a(758)       -      
  109.230     2.568        5.00      9     a(758)       -      
    0.000     2.461       14.00     10     a(758)       -      
    1.719     4.267       14.00     10     a(758)       -      
    0.995     1.909       14.00      1     a(758)       -      
    2.352     3.454       14.00      1     a(758)       -      
    4.431     5.054       14.00      4     a(758)       -      
    5.338     4.292       14.00      2     a(758)       -      
    6.466     3.392       14.00      2     a(758)       -      
    7.140     2.582       14.00      2     a(758)       -      
   10.609     0.857       14.00      5     a(758)       -      
   16.268     0.869       14.00      6     a(758)       -      
   19.055     0.431       14.00      6     a(758)       -      
   25.731     0.301       14.00      6     a(758)       -      
   46.284     0.137       14.00      9     a(758)       -      
   46.269     0.125       14.00      9     a(758)       -      
  103.759     2.803       14.00      8     a(758)       -      
  111.706     3.180       14.00      8     a(758)       -      
    1.701     3.403       23.00      1     a(758)       -      
    2.667     4.893       23.00      1     a(758)       -      
    2.639     4.576       23.00      1     a(758)       -      
    2.639     4.576       23.00      4     a(758)       -      
    4.299     5.307       23.00      4     a(758)       -      
    6.265     4.890       23.00      -     a(758)       -      
    9.530     1.417       23.00      2     a(758)       -      
   15.178     1.164       23.00      5     a(758)       -      
   15.178     1.164       23.00      6     a(758)       -      
   19.581     0.588       23.00      6     a(758)       -      
   22.999     1.869       23.00      5     a(758)       -      
   43.156     0.691       23.00      9     a(758)       -      
  624.367    75.750       23.00      2     a(758)       -      
  101.604     3.175       23.00      2     a(758)       -      
  101.604     3.175       23.00      9     a(758)       -      
    0.000     1.974       25.00      1     a(758)      1.0     
    1.518     4.071       25.00      1     a(758)      1.0     
    1.518     4.071       25.00      4     a(758)      0.04    
    3.430     5.147       25.00      2     a(758)      0.08    
    3.430     5.147       25.00      4     a(758)      0.04    
    7.354     4.487       25.00      2     a(758)      0.08    
    7.354     4.487       25.00      5     a(758)      0.04    
   15.414     1.237       25.00      5     a(758)      0.04    
    0.482     3.505       29.50      1     a(758)       -      
    0.645     3.669       29.50      4     a(758)       -      
    0.852     3.730       29.50      4     a(758)       -      
    1.180     3.799       29.50      4     a(758)       -      
    1.555     3.892       29.50      4     a(758)       -      
    1.784     3.985       29.50      4     a(758)       -      
    2.669     4.443       29.50      4     a(758)       -      
    2.827     4.581       29.50      4     a(758)       -      
    3.157     4.754       29.50      4     a(758)       -      
    3.653     5.008       29.50      4     a(758)       -      
    4.108     4.973       29.50      2     a(758)       -      
    4.200     4.938       29.50      2     a(758)       -      
    4.769     5.019       29.50      2     a(758)       -      
    5.034     5.036       29.50      2     a(758)       -      
    5.768     4.920       29.50      2     a(758)       -      
    6.507     4.894       29.50      2     a(758)       -      
    7.363     4.885       29.50      2     a(758)       -      
    7.595     4.854       29.50      2     a(758)       -      
    8.363     4.937       29.50      2     a(758)       -      
    8.220     4.672       29.50      2     a(758)       -      
    8.221     4.594       29.50      5     a(758)       -      
    8.546     3.159       29.50      5     a(758)       -      
    8.669     3.056       29.50      5     a(758)       -      
   10.547     1.682       29.50      5     a(758)       -      
   11.447     1.471       29.50      5     a(758)       -      
   11.969     1.394       29.50      5     a(758)       -      
   15.185     1.493       29.50      5     a(758)       -      
   15.185     1.493       29.50      6     a(758)       -      
   17.804     1.169       29.50      6     a(758)       -      
   19.409     0.983       29.50      6     a(758)       -      
   22.176     1.007       29.50      6     a(758)       -      
  192.572    20.368       29.50      6     a(758)       -      
  133.187    10.152       29.50      6     a(758)       -      
    4.361     5.542       36.00      4     a(758)       -      
    6.652     5.725       36.00      2     a(758)       -      
    7.831     7.594       36.00      4     a(758)       -      
   10.780     3.096       36.00      5     a(758)       -      
   15.731     2.564       36.00      5     a(758)       -      
   23.369     1.492       36.00      6     a(758)       -      
  123.620     6.625       36.00      2     a(758)       -      
    0.552     3.557       46.00      4     a(758)       -      
    1.045     3.744       46.00      4     a(758)       -      
    1.143     3.773       46.00      4     a(758)       -      
    1.960     4.136       46.00      4     a(758)       -      
    2.850     4.657       46.00      4     a(758)       -      
    2.983     4.724       46.00      4     a(758)       -      
    2.974     4.714       46.00      4     a(758)       -      
    3.262     4.910       46.00      4     a(758)       -      
    3.349     4.948       46.00      4     a(758)       -      
    4.015     5.520       46.00      2     a(758)       -      
    4.022     5.508       46.00      2     a(758)       -      
    4.328     5.551       46.00      2     a(758)       -      
    4.631     5.623       46.00      2     a(758)       -      
    4.973     5.633       46.00      2     a(758)       -      
    5.522     5.775       46.00      2     a(758)       -      
    5.536     5.727       46.00      2     a(758)       -      
    6.118     5.907       46.00      2     a(758)       -      
    7.073     6.031       46.00      2     a(758)       -      
    7.588     6.117       46.00      2     a(758)       -      
    7.956     6.216       46.00      2     a(758)       -      
    8.374     6.336       46.00      2     a(758)       -      
    9.995     6.870       46.00      2     a(758)       -      
   10.242     7.036       46.00      2     a(758)       -      
   10.009     6.940       46.00      2     a(758)       -      
   11.486     7.458       46.00      5     a(758)       -      
   11.501     7.263       46.00      5     a(758)       -      
   11.434     6.694       46.00      5     a(758)       -      
   12.826     4.277       46.00      5     a(758)       -      
   12.977     4.126       46.00      5     a(758)       -      
   13.167     3.995       46.00      5     a(758)       -      
   14.635     3.690       46.00      5     a(758)       -      
   14.525     3.686       46.00      5     a(758)       -      
   15.201     3.625       46.00      5     a(758)       -      
   15.173     2.902       46.00      6     a(758)       -      
   15.365     2.501       46.00      6     a(758)       -      
   16.499     2.094       46.00      6     a(758)       -      
   16.760     2.052       46.00      6     a(758)       -      
   20.071     1.530       46.00      6     a(758)       -      
   20.452     1.447       46.00      6     a(758)       -      
   22.753     1.493       46.00      6     a(758)       -      
   23.574     1.499       46.00      6     a(758)       -      
    1.518     4.285       56.00      4     a(758)       -      
    2.502     4.719       56.00      4     a(758)       -      
    4.267     5.778       56.00      4     a(758)       -      
    6.732     6.829       56.00      2     a(758)       -      
   17.991     4.823       56.00      5     a(758)       -      
   16.438     9.058       56.00      5     a(758)       -      
   22.029     2.911       56.00      6     a(758)       -      
   22.175     2.060       56.00      6     a(758)       -      
   37.802     1.833       56.00      5     a(758)       -      
   43.894     2.249       56.00      9     a(758)       -      
   46.391     1.837       56.00      9     a(758)       -      
  226.697    29.320       56.00      2     a(758)       -      
  113.941     8.789       56.00      2     a(758)       -      
    0.753     3.602       60.00      4     a(758)       -      
    2.518     4.462       60.00      4     a(758)       -      
    2.939     4.727       60.00      4     a(758)       -      
    4.406     5.929       60.00      4     a(758)       -      
    5.491     6.323       60.00      2     a(758)       -      
    6.884     6.773       60.00      2     a(758)       -      
    9.193     7.863       60.00      2     a(758)       -      
   12.694     9.778       60.00      2     a(758)       -      
   16.908     9.235       60.00      2     a(758)       -      
   16.533     8.385       60.00      6     a(758)       -      
   16.841     4.021       60.00      6     a(758)       -      
   17.994     2.978       60.00      6     a(758)       -      
   23.190     2.065       60.00      6     a(758)       -      
   28.801     2.408       60.00      6     a(758)       -      
   49.998     5.311       60.00      6     a(758)       -      
  141.118    20.796       60.00      6     a(758)       -      
  146.516    20.504       60.00      6     a(758)       -      
   44.305     1.244       60.00      6     a(758)       -      
   46.535     1.337       60.00      6     a(758)       -      
  146.858    17.056       60.00      6     a(758)       -      
   59.995     2.626       60.00      6     a(758)       -      
    6.711     8.384       75.00      4     a(758)       -      
    6.711     8.384       75.00      2     a(758)       -      
   12.568    11.571       75.00      2     a(758)       -      
   22.787     5.729       75.00      6     a(758)       -      
   22.787     5.729       75.00      5     a(758)       -      
   25.351     3.065       75.00      5     a(758)       -      
   39.761     4.838       75.00      5     a(758)       -      
   85.784    10.255       75.00      8     a(758)       -      
    1.071     3.614       82.50      4     a(758)       -      
    1.885     4.077       82.50      4     a(758)       -      
    3.687     5.496       82.50      4     a(758)       -      
    4.831     6.532       82.50      4     a(758)       -      
    5.030     6.680       82.50      4     a(758)       -      
    7.120     7.709       82.50      2     a(758)       -      
    9.645     9.376       82.50      2     a(758)       -      
   10.760    10.156       82.50      2     a(758)       -      
   12.805    11.620       82.50      2     a(758)       -      
   17.356    15.070       82.50      2     a(758)       -      
   19.930    17.276       82.50      2     a(758)       -      
   21.605    18.857       82.50      2     a(758)       -      
   20.986    13.778       82.50      6     a(758)       -      
   21.163    11.557       82.50      6     a(758)       -      
   20.483     8.561       82.50      6     a(758)       -      
   20.060     6.461       82.50      6     a(758)       -      
   20.533     7.263       82.50      6     a(758)       -      
   21.757     5.809       82.50      6     a(758)       -      
   21.128     5.213       82.50      6     a(758)       -      
   21.879     4.361       82.50      6     a(758)       -      
   27.691     3.224       82.50      6     a(758)       -      
   29.552     3.707       82.50      6     a(758)       -      
  184.260    43.972       82.50      6     a(758)       -      
   40.469     4.130       82.50      6     a(758)       -      
   41.674     4.006       82.50      6     a(758)       -      
  133.634    27.088       82.50      6     a(758)       -      
   99.277    18.159       82.50      6     a(758)       -      
   58.764     6.169       82.50      6     a(758)       -      
   59.080     6.033       82.50      6     a(758)       -      
    0.000     0.736       12.50      1     a(760)       -      
    1.756     1.969       12.50      1     a(760)       -      
    1.756     1.969       12.50      3     a(760)       -      
    3.754     4.207       12.50      1     a(760)       -      
    3.754     4.207       12.50      3     a(760)       -      
    4.385     4.643       12.50      -     a(760)       -      
    4.385     4.643       12.50      -     a(760)       -      
    4.707     4.442       12.50      -     a(760)       -      
    4.707     4.442       12.50      -     a(760)       -      
    6.068     3.756       12.50      1     a(760)       -      
    6.068     3.756       12.50      3     a(760)       -      
    6.068     3.756       12.50      5     a(760)       -      
    7.206     1.464       12.50      5     a(760)       -      
   11.775     0.580       12.50      5     a(760)       -      
   16.433     0.708       12.50      6     a(760)       -      
   29.236     1.358       12.50      6     a(760)       -      
   29.236     1.358       12.50      8     a(760)       -      
   66.095     3.155       12.50      8     a(760)       -      
  945.937    73.193       12.50      8     a(760)       -      
  241.013    23.206       25.00     12     a(761)      0.0     
   21.453     0.939       25.00     12     a(761)      0.04    
   21.453     0.939       25.00      6     a(761)      0.04    
   15.716     1.193       25.00      6     a(761)      0.04    
   15.716     1.193       25.00      5     a(761)      0.04    
    7.464     4.474       25.00      5     a(761)      0.04    
    7.464     4.474       25.00      2     a(761)      0.08    
    3.381     4.851       25.00      2     a(761)      0.0     
    3.381     4.851       25.00      4     a(761)      0.04    
    1.567     3.902       25.00      4     a(761)      0.04    
    1.567     3.902       25.00      1     a(761)      0.0     
    0.000     1.974       25.00      1     a(761)      1.0     
    1.400     0.986        5.00      1     a(762)       -      
    1.127     0.811        5.00      1     a(762)       -      
    0.920     0.730        5.00      1     a(762)       -      
    0.387     0.581        5.00      1     a(762)       -      
    0.200     0.522        5.00      1     a(762)       -      
    0.000     0.455        5.00      1     a(762)       -      
    3.189     3.817       10.00      1     a(762)       -      
    2.126     1.829       10.00      1     a(762)       -      
    2.028     1.737       10.00      1     a(762)       -      
    1.446     1.276       10.00      1     a(762)       -      
    0.891     1.060       10.00      1     a(762)       -      
    0.868     1.007       10.00      1     a(762)       -      
    0.372     0.805       10.00      1     a(762)       -      
    0.198     0.732       10.00      1     a(762)       -      
    2.693     3.731       15.00      1     a(762)       -      
    2.678     3.757       15.00      1     a(762)       -      
    1.768     2.164       15.00      1     a(762)       -      
    1.347     1.735       15.00      1     a(762)       -      
    0.824     1.392       15.00      1     a(762)       -      
    0.622     1.292       15.00      1     a(762)       -      
    0.348     1.132       15.00      1     a(762)       -      
    0.000     0.942       15.00      1     a(762)       -      
    2.671     4.404       20.00      4     a(762)       -      
    2.331     4.216       20.00      4     a(762)       -      
    2.240     4.186       20.00      1     a(762)       -      
    1.609     2.792       20.00      1     a(762)       -      
    0.731     1.850       20.00      1     a(762)       -      
    0.557     1.717       20.00      1     a(762)       -      
    0.316     1.553       20.00      1     a(762)       -      
    0.172     1.463       20.00      1     a(762)       -      
    2.451     4.286       25.00      4     a(763)      0.04    
    1.470     3.944       25.00      4     a(763)      0.04    
    1.470     3.944       25.00      1     a(763)      1.0     
    1.414     3.846       25.00      1     a(763)      1.0     
    1.123     3.245       25.00      1     a(763)      1.0     
    0.855     2.802       25.00      1     a(763)      1.0     
    0.452     2.361       25.00      1     a(763)      1.0     
    0.345     2.261       25.00      1     a(763)      1.0     
    0.186     2.123       25.00      1     a(763)      1.0     
    0.081     2.028       25.00      1     a(763)      1.0     
    0.000     1.982       25.00      1     a(763)      1.0     
   17.908     0.832       25.00      6     a(764)      0.04    
   14.264     1.182       25.00      6     a(764)      0.04    
   14.264     1.182       25.00      5     a(764)      0.04    
    6.875     4.142       25.00      5     a(764)      0.0     
    6.875     4.142       25.00      2     a(764)      0.08    
    5.519     4.454       25.00      2     a(764)      0.08    
    5.519     4.454       25.00      7     a(764)      0.0     
    5.449     4.436       25.00      2     a(764)      0.08    
    5.449     4.436       25.00      7     a(764)      0.0     
    2.913     4.358       25.00      7     a(764)      0.0     
    2.913     4.358       25.00      4     a(764)      0.0     
    1.533     3.899       25.00      4     a(764)      0.04    
    1.533     3.899       25.00      1     a(764)      0.0     
    0.000     1.974       25.00      1     a(764)      1.0     
    0.000     1.974       25.00      1     a(765)      1.0     
    1.547     4.127       25.00      1     a(765)      1.0     
    1.547     4.127       25.00      4     a(765)      0.04    
    3.414     5.101       25.00      4     a(765)      0.04    
    3.414     5.101       25.00      2     a(765)      0.08    
    7.064     4.222       25.00      2     a(765)      0.08    
    7.064     4.222       25.00      5     a(765)      0.04    
    8.475     2.650       25.00      5     a(765)      0.04    
    9.596     1.639       25.00      5     a(765)      0.04    
   12.576     1.249       25.00      5     a(765)      0.04    
   15.141     1.431       25.00      5     a(765)      0.04    
   15.141     1.431       25.00      6     a(765)      0.04    
  142.685     7.994       25.00      3     a(765)      0.0     
  956.408   123.645       25.00      3     a(765)      0.0     
  270.281    11.597       25.00     45     a(765)      0.0     
 2011.310   102.163       25.00     45     a(765)      0.0     
    0.000     0.309        0.00      1     a(765)       -      
    0.183     0.371        0.00      1     a(765)       -      
    0.401     0.426        0.00      1     a(765)       -      
    0.634     0.470        0.00      1     a(765)       -      
    1.490     0.685        0.00      1     a(765)       -      
    2.084     0.785        0.00      1     a(765)       -      
    2.427     0.860        0.00      1     a(765)       -      
    3.088     1.265        0.00      1     a(765)       -      
    3.355     1.478        0.00      1     a(765)       -      
    3.640     1.839        0.00      1     a(765)       -      
    3.791     2.107        0.00      1     a(765)       -      
    3.868     2.417        0.00      1     a(765)       -      
    3.966     2.640        0.00      1     a(765)       -      
    4.273     3.463        0.00      1     a(765)       -      
    4.532     4.054        0.00      1     a(765)       -      
    4.532     4.054        0.00      2     a(765)       -      
    4.689     4.105        0.00      2     a(765)       -      
    4.816     4.142        0.00      2     a(765)       -      
    5.156     3.895        0.00      2     a(765)       -      
    5.295     3.886        0.00      2     a(765)       -      
    5.523     3.814        0.00      2     a(765)       -      
    5.523     3.814        0.00      5     a(765)       -      
    5.513     3.293        0.00      5     a(765)       -      
    5.469     2.713        0.00      5     a(765)       -      
    5.680     2.301        0.00      5     a(765)       -      
    5.829     2.114        0.00      5     a(765)       -      
    8.530     0.902        0.00      5     a(765)       -      
   11.636     0.526        0.00      5     a(765)       -      
   12.972     0.525        0.00      5     a(765)       -      
   15.804     0.634        0.00      5     a(765)       -      
   17.574     0.770        0.00      5     a(765)       -      
   17.574     0.770        0.00      6     a(765)       -      
   18.388     0.748        0.00      6     a(765)       -      
   19.379     1.050        0.00      6     a(765)       -      
   19.379     1.050        0.00      3     a(765)       -      
   19.682     0.704        0.00      3     a(765)       -      
   20.314     0.623        0.00      3     a(765)       -      
   37.177     0.960        0.00      3     a(765)       -      
   46.832     1.039        0.00      3     a(765)       -      
   46.241     0.763        0.00     11     a(765)       -      
   95.064     1.197        0.00     11     a(765)       -      
   95.064     1.197        0.00     12     a(765)       -      
  122.633     3.425        0.00     12     a(765)       -      
  260.965    15.664        0.00     12     a(765)       -      
  240.268    14.306        0.00     12     a(765)       -      
  102.758     1.381        0.00     12     a(765)       -      
  102.758     1.381        0.00     45     a(765)       -      
  122.927     1.580        0.00     45     a(765)       -      
  122.927     1.580        0.00     55     a(765)       -      
  186.401     4.502        0.00     55     a(765)       -      
  925.181    44.383        0.00     55     a(765)       -      
  139.927     1.739        0.00     45     a(765)       -      
  193.154     2.399        0.00     45     a(765)       -      
  319.625     4.624        0.00     45     a(765)       -      
 1331.970    37.710        0.00     45     a(765)       -      
 1947.530    56.325        0.00     45     a(765)       -      
    2.549     0.239      -12.00     -      a(759)       -      
    3.141     0.268      -10.50     -      a(759)       -      
    3.977     1.732       -4.00     -      a(759)       -      
    3.497     0.732       -4.00     -      a(759)       -      
    2.284     0.437       -4.00     -      a(759)       -      
    1.468     0.380       -4.00     -      a(759)       -      
    3.671     2.570        2.00     -      a(759)       -      
    3.304     1.422        2.00     -      a(759)       -      
    1.468     0.620        2.00     -      a(759)       -      
    1.203     0.577        2.00     -      a(759)       -      
    0.000     0.394        2.00     -      a(759)       -      
    2.651     2.042        8.00     -      a(759)       -      
    1.958     1.267        8.00     -      a(759)       -      
    1.366     0.986        8.00     -      a(759)       -      
    1.060     0.873        8.00     -      a(759)       -      
    0.000     0.563        8.00     -      a(759)       -      
    0.0000    0.7416      12.0      1         b         -      
    0.0000    0.7339      12.0      1         b         -      
    3.3316    4.5924      12.0      1         b         -      
    3.3303    4.5795      12.0      1         b         -      
    3.3316    4.5924      12.0      2         b         -      
    3.3303    4.5795      12.0      2         b         -      
    6.1100    3.8295      12.0      2         b         -      
    6.1192    3.8459      12.0      2         b         -      
    6.1100    3.8295      12.0      5         b         -      
    6.1192    3.8295      12.0      5         b         -      
   16.2541    0.8266      12.0      5         b         -      
    0.0000    1.9742      25.0      1         b        1.0     
    1.5175    4.0672      25.0      1         b        1.0     
    1.5185    4.0749      25.0      1         b        1.0     
    1.5175    4.0672      25.0      4         b        0.04    
    1.5185    4.0749      25.0      4         b        0.04    
    3.4128    5.1045      25.0      2         b        0.08    
    3.4475    5.1919      25.0      2         b        0.08    
    3.4128    5.1045      25.0      4         b        0.04    
    3.4475    5.1919      25.0      4         b        0.04    
    7.3773    4.5177      25.0      2         b        0.08    
    7.3308    4.4557      25.0      2         b        0.08    
    7.3773    4.5177      25.0      5         b        0.04    
    7.3308    4.4557      25.0      5         b        0.04    
   15.4139    1.2374      25.0      5         b        0.04

Notes and References

Prefix m denotes molality; t - experimental temperature (^oC); solid - identity of the solid which the solution is saturated with respect to; ref. - source of data; weight - the weight given to the data point in the fit of the model (normalised).
Solids: 0 = ice, 1 = Na2SO4.10H2O(s), 2 = Na2H(SO4)2(s), 3 = NaHSO4.5H2O(s) 4 = Na2SO4(s), 5 = NaHSO4.H2O(s), 6 = NaHSO4(s), 7 = Na3H(SO4)2.H2O(s), 8 = NaH3(SO4)2(s), 9 = NaH3(SO4)2.(1.5H2O), 10 = Na2SO4.7H2O(s), 12 = NaH3(SO4)2.H2O(s), 11 = H2SO4.H2O(s), 45 = Na2SO4.(4.5H2O)(s), 55 = Na2SO4.(5.5H2O)(s).
Sources: a - H. L. Silcock, Solubilities of Inorganic and Organic Compounds, Vol. 3, Pergamon, Oxford, 1979, (the table numbers are given in parentheses); b - H. W. Foote (1925) Am. J. Sci. [5] 9, 441-447.

(2) Osmotic Coefficients from Isopiestic Measurements

    mH2SO4     mNa2SO4     osm           t     ref.        weight
    0.12051    0.07212     0.6711      25.0     c           1.0  
    0.14618    0.04863     0.6635      25.0     c           1.0  
    0.17069    0.02432     0.6629      25.0     c           1.0  
    0.12593    0.07536     0.6718      25.0     c           1.0  
    0.15258    0.05076     0.6650      25.0     c           1.0  
    0.17821    0.02539     0.6642      25.0     c           1.0  
    0.25257    0.15115     0.6563      25.0     c           1.0  
    0.30216    0.10052     0.6580      25.0     c           1.0  
    0.35071    0.04997     0.6613      25.0     c           1.0  
    0.42028    0.25151     0.6545      25.0     c           1.0  
    0.49707    0.16535     0.6637      25.0     c           1.0  
    0.57094    0.08135     0.6740      25.0     c           1.0  
    0.51711    0.30946     0.6600      25.0     c           1.0  
    0.60785    0.20220     0.6735      25.0     c           1.0  
    0.69559    0.09911     0.6865      25.0     c           1.0  
    0.61281    0.36673     0.6621      25.0     c           1.0  
    0.71719    0.23858     0.6786      25.0     c           1.0  
    0.81679    0.11638     0.6950      25.0     c           1.0  
    0.71632    0.42868     0.6666      25.0     c           1.0  
    0.83360    0.27730     0.6871      25.0     c           1.0  
    0.94523    0.13467     0.7068      25.0     c           1.0  
    0.81060    0.48510     0.6759      25.0     c           1.0  
    0.94000    0.31270     0.6991      25.0     c           1.0  
    1.06278    0.15142     0.7213      25.0     c           1.0  
    0.91051    0.54489     0.6867      25.0     c           1.0  
    1.05128    0.34972     0.7133      25.0     c           1.0  
    1.18541    0.16890     0.7379      25.0     c           1.0  
    1.01368    0.60662     0.6928      25.0     c           1.0  
    1.16692    0.38818     0.7219      25.0     c           1.0  
    1.31118    0.18682     0.7494      25.0     c           1.0  
    1.10414    0.66076     0.7035      25.0     c           1.0  
    1.26664    0.42136     0.7356      25.0     c           1.0  
    1.42226    0.20264     0.7641      25.0     c           1.0  
    1.18403    0.70857     0.7093      25.0     c           1.0  
    1.35556    0.45094     0.7431      25.0     c           1.0  
    1.51548    0.21592     0.7753      25.0     c           1.0  
    1.20580    0.72160     0.7103      25.0     c           1.0  
    1.37890    0.45870     0.7450      25.0     c           1.0  
    1.54147    0.21963     0.7774      25.0     c           1.0  
    1.35438    0.81052     0.7257      25.0     c           1.0  
    1.54263    0.51317     0.7643      25.0     c           1.0  
    1.71898    0.24492     0.8000      25.0     c           1.0  
    1.48094    0.88626     0.7398      25.0     c           1.0  
    1.68130    0.55930     0.7816      25.0     c           1.0  
    1.86752    0.26608     0.8208      25.0     c           1.0  
    1.58386    0.94784     0.7514      25.0     c           1.0  
    1.79416    0.59684     0.7956      25.0     c           1.0  
    1.98953    0.28347     0.8369      25.0     c           1.0  
    1.71010    1.02340     0.7633      25.0     c           1.0  
    1.93118    0.64242     0.8107      25.0     c           1.0  
    2.13606    0.30434     0.8550      25.0     c           1.0  
    1.81934    1.08876     0.7755      25.0     c           1.0  
    2.04944    0.68176     0.8257      25.0     c           1.0  
    2.26044    0.32206     0.8733      25.0     c           1.0  
    1.91800    1.14780     0.7865      25.0     c           1.0  
    2.15502    0.71688     0.8396      25.0     c           1.0  
    2.37554    0.33846     0.8885      25.0     c           1.0  
    2.01471    1.20569     0.7964      25.0     c           1.0  
    2.25962    0.75168     0.8517      25.0     c           1.0  
    2.48512    0.35408     0.9033      25.0     c           1.0  
    2.10818    1.26162     0.8063      25.0     c           1.0  
    2.35882    0.78468     0.8643      25.0     c           1.0  
    2.59025    0.36905     0.9181      25.0     c           1.0  
    2.18388    1.30692     0.8138      25.0     c           1.0  
    2.44009    0.81171     0.8737      25.0     c           1.0  
    2.67672    0.38138     0.9290      25.0     c           1.0  
    2.28354    1.36656     0.8247      25.0     c           1.0  
    2.54634    0.84706     0.8870      25.0     c           1.0  
    2.78789    0.39721     0.9450      25.0     c           1.0  
    2.39133    1.43107     0.8350      25.0     c           1.0  
    2.66025    0.88495     0.9003      25.0     c           1.0  
    2.90745    0.41425     0.9608      25.0     c           1.0  
    2.46741    1.47659     0.8431      25.0     c           1.0  
    2.73986    0.91144     0.9106      25.0     c           1.0  
    2.99008    0.42602     0.9733      25.0     c           1.0  
    2.49312    1.49198     0.8458      25.0     c           1.0  
    2.76673    0.92037     0.9141      25.0     c           1.0  
    3.01931    0.43019     0.9771      25.0     c           1.0  
    2.49168    1.49112     0.8465      25.0     c           1.0  
    2.76447    0.91963     0.9151      25.0     c           1.0  
    3.01800    0.43000     0.9778      25.0     c           1.0  
    2.56525    1.53515     0.8525      25.0     c           1.0  
    2.84296    0.94574     0.9226      25.0     c           1.0  
    3.09783    0.44137     0.9876      25.0     c           1.0  
    2.62569    1.57131     0.8582      25.0     c           1.0  
    2.90510    0.96640     0.9304      25.0     c           1.0  
    3.16304    0.45067     0.9968      25.0     c           1.0  
    2.73079    1.63421     0.8684      25.0     c           1.0  
    3.01398    1.00262     0.9438      25.0     c           1.0  
    3.27560    0.46670     1.0130      25.0     c           1.0  
    2.84359    1.70171     0.8785      25.0     c           1.0  
    3.13111    1.04159     0.9569      25.0     c           1.0  
    3.39586    0.48384     1.0292      25.0     c           1.0  
    2.97396    1.77974     0.8900      25.0     c           1.0  
    3.26400    1.08580     0.9726      25.0     c           1.0  
    3.53180    0.50321     1.0485      25.0     c           1.0  
    2.92961    1.75319     0.8852      25.0     c           1.0  
    3.21883    1.07077     0.9663      25.0     c           1.0  
    3.48523    0.49657     1.0410      25.0     c           1.0  
    2.95469    1.76821     0.8874      25.0     c           1.0  
    3.24442    1.07928     0.9694      25.0     c           1.0  
    3.51088    0.50022     1.0449      25.0     c           1.0  
    2.99454    1.79206     0.8910      25.0     c           1.0  
    3.28479    1.09271     0.9743      25.0     c           1.0  
    3.55271    0.50619     1.0507      25.0     c           1.0  
    3.04785    1.82395     0.8950      25.0     c           1.0  
    3.33837    1.11053     0.9801      25.0     c           1.0  
    3.60812    0.51408     1.0578      25.0     c           1.0  
    3.10634    1.85896     0.8999      25.0     c           1.0  
    3.39840    1.13050     0.9867      25.0     c           1.0  
    3.66922    0.52278     1.0660      25.0     c           1.0  
    3.19480    1.91190     0.9065      25.0     c           1.0  
    3.48747    1.16013     0.9961      25.0     c           1.0  
    3.75998    0.53572     1.0777      25.0     c           1.0  
    3.29747    1.97333     0.9147      25.0     c           1.0  
    3.59072    1.19448     1.0076      25.0     c           1.0  
    3.86265    0.55035     1.0925      25.0     c           1.0  
    3.39650    2.03260     0.9217      25.0     c           1.0  
    3.68932    1.22728     1.0178      25.0     c           1.0  
    3.96121    0.56439     1.1057      25.0     c           1.0  
    3.50317    2.09643     0.9292      25.0     c           1.0  
    3.79415    1.26215     1.0290      25.0     c           1.0  
    4.06660    0.57940     1.1199      25.0     c           1.0  
    3.57605    2.14005     0.9336      25.0     c           1.0  
    3.86633    1.28617     1.0357      25.0     c           1.0  
    4.13785    0.58955     1.1289      25.0     c           1.0  
    3.71106    2.22084     0.9415      25.0     c           1.0  
    3.99802    1.32998     1.0483      25.0     c           1.0  
    4.26879    0.60821     1.1452      25.0     c           1.0  
    3.82448    2.28872     0.9479      25.0     c           1.0  
    4.10781    1.36649     1.0585      25.0     c           1.0  
    4.37715    0.62365     1.1587      25.0     c           1.0  
    3.93308    2.35372     0.9536      25.0     c           1.0  
    4.21211    1.40119     1.0680      25.0     c           1.0  
    4.47877    0.63813     1.1716      25.0     c           1.0  
    4.03024    2.41186     0.9587      25.0     c           1.0  
    4.30583    1.43237     1.0764      25.0     c           1.0  
    4.56928    0.65102     1.1831      25.0     c           1.0  
    4.15705    2.48775     0.9639      25.0     c           1.0  
    4.42552    1.47218     1.0860      25.0     c           1.0  
    4.68578    0.66762     1.1964      25.0     c           1.0  
    4.26503    2.55237     0.9690      25.0     c           1.0  
    4.52614    1.50566     1.0952      25.0     c           1.0  
    4.78276    0.68144     1.2089      25.0     c           1.0  
    4.36288    2.61092     0.9726      25.0     c           1.0  
    4.61821    1.53629     1.1021      25.0     c           1.0  
    4.87073    0.69397     1.2189      25.0     c           1.0  
    4.52960    2.71070     0.9783      25.0     c           1.0  
    4.77294    1.58776     1.1136      25.0     c           1.0  
    5.01786    0.71494     1.2356      25.0     c           1.0  
    4.66793    2.79347     0.9829      25.0     c           1.0  
    4.90051    1.63019     1.1230      25.0     c           1.0  
    5.13953    0.73227     1.2490      25.0     c           1.0  
    4.81175    2.87955     0.9869      25.0     c           1.0  
    5.03152    1.67378     1.1321      25.0     c           1.0  
    5.26233    0.74977     1.2626      25.0     c           1.0  
    4.94726    2.96064     0.9903      25.0     c           1.0  
    5.15346    1.71434     1.1403      25.0     c           1.0  
    5.37682    0.76608     1.2748      25.0     c           1.0  
    5.08108    3.04072     0.9931      25.0     c           1.0  
    5.27435    1.75455     1.1475      25.0     c           1.0  
    5.48859    0.78201     1.2863      25.0     c           1.0  
    5.23166    3.13084     0.9961      25.0     c           1.0  
    5.40821    1.79909     1.1558      25.0     c           1.0  
    5.61140    0.79950     1.2994      25.0     c           1.0  
    5.34734    3.20006     0.9981      25.0     c           1.0  
    5.50989    1.83291     1.1618      25.0     c           1.0  
    5.70593    0.81297     1.3086      25.0     c           1.0  
    5.44156    3.25644     0.9996      25.0     c           1.0  
    5.59558    1.86142     1.1659      25.0     c           1.0  
    5.78383    0.82407     1.3157      25.0     c           1.0  
    5.58751    3.34379     1.0018      25.0     c           1.0  
    5.72487    1.90443     1.1728      25.0     c           1.0  
    5.89875    0.84045     1.3277      25.0     c           1.0  
    5.75273    3.44267     1.0031      25.0     c           1.0  
    5.86459    1.95091     1.1802      25.0     c           1.0  
    6.02926    0.85904     1.3390      25.0     c           1.0  
    5.88399    3.52121     1.0041      25.0     c           1.0  
    5.97933    1.98907     1.1852      25.0     c           1.0  
    6.13106    0.87354     1.3483      25.0     c           1.0  
    6.03000    3.60860     1.0057      25.0     c           1.0  
    6.10554    2.03106     1.1914      25.0     c           1.0  
    6.24589    0.88991     1.3585      25.0     c           1.0  
    6.17458    3.69512     1.0063      25.0     c           1.0  
    6.22793    2.07177     1.1967      25.0     c           1.0  
    6.35452    0.90538     1.3681      25.0     c           1.0  
    6.29676    3.76824     1.0070      25.0     c           1.0  
    6.33201    2.10639     1.2012      25.0     c           1.0  
    6.44756    0.91864     1.3760      25.0     c           1.0  
    6.43252    3.84948     1.0076      25.0     c           1.0  
    6.44636    2.14444     1.2060      25.0     c           1.0  
    6.55050    0.93331     1.3844      25.0     c           1.0  
    6.57328    3.93372     1.0078      25.0     c           1.0  
    6.56590    2.18420     1.2101      25.0     c           1.0  
    6.65465    0.94815     1.3927      25.0     c           1.0  
    6.72718    4.02582     1.0081      25.0     c           1.0  
    6.69519    2.22721     1.2149      25.0     c           1.0  
    6.76800    0.96430     1.4019      25.0     c           1.0  
    6.85919    4.10481     1.0072      25.0     c           1.0  
    6.80595    2.26405     1.2175      25.0     c           1.0  
    6.86429    0.97801     1.4081      25.0     c           1.0  
    7.01121    4.19579     1.0080      25.0     c           1.0  
    6.93216    2.30604     1.2228      25.0     c           1.0  
    6.97536    0.99384     1.4175      25.0     c           1.0  
    7.17762    4.29538     1.0085      25.0     c           1.0  
    7.07166    2.35244     1.2277      25.0     c           1.0  
    7.09694    1.01116     1.4270      25.0     c           1.0  
    7.33778    4.39122     1.0080      25.0     c           1.0  
    7.20260    2.39600     1.2317      25.0     c           1.0  
    7.21169    1.02751     1.4350      25.0     c           1.0  
    7.48104    4.47696     1.0079      25.0     c           1.0  
    7.32116    2.43544     1.2353      25.0     c           1.0  
    7.31209    1.04181     1.4427      25.0     c           1.0  
    7.65747    4.58253     1.0063      25.0     c           1.0  
    7.46478    2.48322     1.2382      25.0     c           1.0  
    7.43769    1.05971     1.4495      25.0     c           1.0  
    7.85766    4.70234     1.0052      25.0     c           1.0  
    7.62536    2.53664     1.2424      25.0     c           1.0  
    7.57616    1.07944     1.4587      25.0     c           1.0  
    8.01594    4.79706     1.0052      25.0     c           1.0  
    7.75518    2.57982     1.2463      25.0     c           1.0  
    7.68478    1.09492     1.4670      25.0     c           1.0  
    7.87674    2.62026     1.2487      25.0     c           1.0  
    7.79061    1.10999     1.4727      25.0     c           1.0  
    8.04257    2.67543     1.2527      25.0     c           1.0  
    7.93153    1.13007     1.4817      25.0     c           1.0  
    8.26243    2.74857     1.2583      25.0     c           1.0  
    8.11770    1.15660     1.4939      25.0     c           1.0  
    8.45378    2.81222     1.2621      25.0     c           1.0  
    8.27832    1.17948     1.5033      25.0     c           1.0  
    8.64138    2.87462     1.2654      25.0     c           1.0  
    8.43762    1.20218     1.5117      25.0     c           1.0  
    8.86724    2.94976     1.2697      25.0     c           1.0  
    8.62633    1.22907     1.5225      25.0     c           1.0  
    9.06234    3.01466     1.2738      25.0     c           1.0  
    8.79316    1.25284     1.5313      25.0     c           1.0  
    9.23568    3.07232     1.2765      25.0     c           1.0  
    8.93671    1.27329     1.5389      25.0     c           1.0  
    9.43528    3.13872     1.2800      25.0     c           1.0  
    9.10214    1.29686     1.5477      25.0     c           1.0  
    9.61012    3.19688     1.2827      25.0     c           1.0  
    9.24831    1.31769     1.5548      25.0     c           1.0  
    9.83448    3.27152     1.2857      25.0     c           1.0  
    9.43563    1.34437     1.5631      25.0     c           1.0  
   10.08740    3.35564     1.2894      25.0     c           1.0  
    9.64307    1.37393     1.5734      25.0     c           1.0  
   10.30200    3.42703     1.2928      25.0     c           1.0  
    9.81988    1.39912     1.5821      25.0     c           1.0  
   10.49030    3.48969     1.2953      25.0     c           1.0  
    9.97480    1.42120     1.5890      25.0     c           1.0  
   10.66370    3.54735     1.2969      25.0     c           1.0  
   10.11750    1.44152     1.5945      25.0     c           1.0  
   10.75140    3.57656     1.2989      25.0     c           1.0  
   10.18840    1.45162     1.5988      25.0     c           1.0  
   10.92700    3.63497     1.3024      25.0     c           1.0  
   10.33810    1.47295     1.6057      25.0     c           1.0  
   13.29450    4.42252     1.0827      25.0     c           0.0
   10.42820    1.48579     1.6100      25.0     c           1.0  
   11.22570    3.73432     1.3049      25.0     c           1.0  
   10.58050    1.50749     1.6149      25.0     c           1.0  
    0.02382    0.13413     0.7387      25.0     c           1.0  
    0.07428    0.09299     0.6976      25.0     c           1.0  
    0.04864    0.11452     0.7151      25.0     c           1.0  
    0.04775    0.26892     0.7007      25.0     c           1.0  
    0.14744    0.18460     0.6683      25.0     c           1.0  
    0.09708    0.22857     0.6814      25.0     c           1.0  
    0.05756    0.32416     0.6894      25.0     c           1.0  
    0.17644    0.22091     0.6623      25.0     c           1.0  
    0.11663    0.27461     0.6726      25.0     c           1.0  
    0.05887    0.33149     0.6897      25.0     c           1.0  
    0.18095    0.22655     0.6607      25.0     c           1.0  
    0.11937    0.28104     0.6724      25.0     c           1.0  
    0.07429    0.41834     0.6755      25.0     c           1.0  
    0.22580    0.28271     0.6544      25.0     c           1.0  
    0.14991    0.35294     0.6617      25.0     c           1.0  
    0.10266    0.57810     0.6572      25.0     c           1.0  
    0.30685    0.38417     0.6475      25.0     c           1.0  
    0.20553    0.48391     0.6490      25.0     c           1.0  
    0.12020    0.67687     0.6484      25.0     c           1.0  
    0.35550    0.44508     0.6455      25.0     c           1.0  
    0.23950    0.56390     0.6433      25.0     c           1.0  
    0.13856    0.78030     0.6405      25.0     c           1.0  
    0.40617    0.50852     0.6434      25.0     c           1.0  
    0.27465    0.64666     0.6388      25.0     c           1.0  
    0.15605    0.87875     0.6353      25.0     c           1.0  
    0.45364    0.56796     0.6435      25.0     c           1.0  
    0.30840    0.72611     0.6355      25.0     c           1.0  
    0.17606    0.99144     0.6302      25.0     c           1.0  
    0.50733    0.63517     0.6440      25.0     c           1.0  
    0.34655    0.81595     0.6329      25.0     c           1.0  
    0.20111    1.13249     0.6258      25.0     c           1.0  
    0.57411    0.71879     0.6455      25.0     c           1.0  
    0.39434    0.92846     0.6309      25.0     c           1.0  
    0.23695    1.33435     0.6221      25.0     c           1.0  
    0.66905    0.83765     0.6488      25.0     c           1.0  
    0.46264    1.08926     0.6299      25.0     c           1.0  
    0.26001    1.46419     0.6211      25.0     c           1.0  
    0.73011    0.91409     0.6514      25.0     c           1.0  
    0.50628    1.19202     0.6306      25.0     c           1.0  
    0.28457    1.60253     0.6219      25.0     c           1.0  
    0.79507    0.99543     0.6555      25.0     c           1.0  
    0.55353    1.30327     0.6321      25.0     c           1.0  
    0.30311    1.70689     0.6200      25.0     c           1.0  
    0.83925    1.05075     0.6593      25.0     c           1.0  
    0.58599    1.37971     0.6339      25.0     c           1.0  
    0.33318    1.87622     0.6271      25.0     c           1.0  
    0.92522    1.15838     0.6649      25.0     c           1.0  
    0.64749    1.52451     0.6379      25.0     c           1.0  
    0.36156    2.03604     0.6309      25.0     c           1.0  
    1.00218    1.25472     0.6702      25.0     c           1.0  
    0.70279    1.65471     0.6416      25.0     c           1.0  
    0.39299    2.21302     0.6365      25.0     c           1.0  
    1.08779    1.36191     0.6771      25.0     c           1.0  
    0.76450    1.80000     0.6468      25.0     c           1.0  
    0.42164    2.37436     0.6428      25.0     c           1.0  
    1.16719    1.46131     0.6838      25.0     c           1.0  
    0.82162    1.93448     0.6521      25.0     c           1.0  
    0.44367    2.49843     0.6492      25.0     c           1.0  
    1.22922    1.53898     0.6900      25.0     c           1.0  
    0.86604    2.03906     0.6575      25.0     c           1.0  
    0.47279    2.66241     0.6573      25.0     c           1.0  
    1.31212    1.64278     0.6974      25.0     c           1.0  
    0.92530    2.17860     0.6639      25.0     c           1.0  
    0.50162    2.82478     0.6655      25.0     c           1.0  
    1.39596    1.74774     0.7042      25.0     c           1.0  
    0.98505    2.31926     0.6699      25.0     c           1.0  
    0.50690    2.85450     0.6662      25.0     c           1.0  
    1.40990    1.76520     0.7053      25.0     c           1.0  
    0.99527    2.34333     0.6707      25.0     c           1.0  
    0.52288    2.94452     0.6718      25.0     c           1.0  
    1.45679    1.82391     0.7100      25.0     c           1.0  
    1.02863    2.42187     0.6751      25.0     c           1.0  
    0.53658    3.02162     0.6767      25.0     c           1.0  
    1.49756    1.87494     0.7140      25.0     c           1.0  
    1.05763    2.49017     0.6787      25.0     c           1.0  
    0.55122    3.10408     0.6817      25.0     c           1.0  
    1.54116    1.92954     0.7179      25.0     c           1.0  
    1.08870    2.56330     0.6823      25.0     c           1.0  
    0.56981    3.20879     0.6875      25.0     c           1.0  
    1.59685    1.99925     0.7224      25.0     c           1.0  
    1.12826    2.65644     0.6864      25.0     c           1.0  
    0.59355    3.34245     0.6961      25.0     c           1.0  
    1.67056    2.09154     0.7283      25.0     c           1.0  
    1.18001    2.77829     0.6922      25.0     c           1.0  
    0.61701    3.47459     0.7050      25.0     c           1.0  
    1.74343    2.18277     0.7347      25.0     c           1.0  
    1.23125    2.89895     0.6984      25.0     c           1.0  
    1.79880    2.25210     0.7385      25.0     c           1.0  
    1.27004    2.99026     0.7022      25.0     c           1.0  
    0.63810    3.59330     0.7127      25.0     c           1.0  
    1.80906    2.26494     0.7403      25.0     c           1.0  
    1.27770    3.00830     0.7036      25.0     c           1.0  
    0.66480    3.74370     0.7219      25.0     c           1.0  
    1.89312    2.37018     0.7465      25.0     c           1.0  
    1.33658    3.14692     0.7098      25.0     c           1.0  
    1.95329    2.44551     0.7504      25.0     c           1.0  
    1.37885    3.24645     0.7136      25.0     c           1.0  
    1.98868    2.48982     0.7535      25.0     c           1.0  
    1.40326    3.30394     0.7168      25.0     c           1.0  
    0.69454    3.91116     0.7328      25.0     c           1.0  
    1.99014    2.49166     0.7531      25.0     c           1.0  
    1.40398    3.30562     0.7167      25.0     c           1.0  
    2.08446    2.60974     0.7591      25.0     c           1.0  
    1.47019    3.46151     0.7226      25.0     c           1.0  
    2.25808    2.82712     0.7695      25.0     c           1.0  
    1.59155    3.74725     0.7329      25.0     c           1.0  
    2.45466    2.45594     0.7968      25.0     c           1.0  
    2.37043    2.96777     0.7758      25.0     c           1.0  
    1.67019    3.93241     0.7392      25.0     c           1.0  
    2.57273    2.57407     0.8047      25.0     c           1.0  
    2.49183    3.11977     0.7813      25.0     c           1.0  
    1.75488    4.13182     0.7448      25.0     c           1.0  
    2.69925    2.70065     0.8120      25.0     c           1.0  
    2.58655    3.23835     0.7849      25.0     c           1.0  
    1.82026    4.28574     0.7488      25.0     c           1.0  
    2.79742    2.79888     0.8170      25.0     c           1.0  
    2.72145    3.40725     0.7890      25.0     c           1.0  
    2.93839    2.93991     0.8227      25.0     c           1.0  
    2.88366    3.61034     0.7944      25.0     c           1.0  
    3.10594    3.10756     0.8303      25.0     c           1.0  
    2.93575    3.67555     0.7942      25.0     c           1.0  
    3.15993    3.16157     0.8306      25.0     c           1.0  
    0.11598    0.11605     0.6773      25.0     c           1.0  
    0.13372    0.13380     0.6717      25.0     c           1.0  
    0.15881    0.15889     0.6653      25.0     c           1.0  
    0.29192    0.29208     0.6513      25.0     c           1.0  
    0.31675    0.31691     0.6500      25.0     c           1.0  
    0.40375    0.40396     0.6482      25.0     c           1.0  
    0.41598    0.41619     0.6481      25.0     c           1.0  
    0.78754    0.78796     0.6609      25.0     c           1.0  
    0.79589    0.79631     0.6611      25.0     c           1.0  
    0.82704    0.82746     0.6644      25.0     c           1.0  
    0.96950    0.97000     0.6740      25.0     c           1.0  
    1.03828    1.03882     0.6794      25.0     c           1.0  
    1.12736    1.12794     0.6867      25.0     c           1.0  
    1.20434    1.20496     0.6918      25.0     c           1.0  
    1.30081    1.30149     0.7024      25.0     c           1.0  
    1.38309    1.38381     0.7088      25.0     c           1.0  
    1.45647    1.45723     0.7174      25.0     c           1.0  
    1.51326    1.51404     0.7228      25.0     c           1.0  
    1.55824    1.55906     0.7255      25.0     c           1.0  
    1.65767    1.65853     0.7344      25.0     c           1.0  
    1.74030    1.74120     0.7421      25.0     c           1.0  
    1.84957    1.85053     0.7519      25.0     c           1.0  
    1.94854    1.94956     0.7600      25.0     c           1.0  
    2.04417    2.04523     0.7676      25.0     c           1.0  
    2.15594    2.15706     0.7766      25.0     c           1.0  
    2.25611    2.25729     0.7836      25.0     c           1.0  
    2.38623    2.38747     0.7929      25.0     c           1.0  
    2.52549    2.52681     0.8021      25.0     c           1.0  
    2.55733    2.55867     0.8039      25.0     c           1.0

Notes and References

Prefix m denotes molality; t - experimental temperature (^oC); osm - stoichiometric molal osmotic coefficient; ref. - source of data; weight - the weight given to the data point in the fit of the model (normalised).
Sources: c - J. A. Rard (1989) J. Chem. Thermodyn. 21, 539-560; and J. A. Rard (1992) J. Chem. Thermodyn. 24, 45-66.

(3) Electromotive Force Measurements

  mH2SO4       mNa2SO4          t       E      ref.   weight 
  5.1890E-3    1.5051E-2      25.0   0.81130    d       1.0  
  5.8825E-3    1.7063E-2      25.0   0.80817    d       1.0  
  9.9650E-3    2.8904E-2      25.0   0.79495    d       1.0  
  1.4750E-2    4.2780E-2      25.0   0.78604    d       1.0  
  2.1904E-2    6.3532E-2      25.0   0.77692    d       1.0  
  2.8007E-2    8.1357E-2      25.0   0.77182    d       1.0  
  0.10         0.10           25.0   0.73933    e       0.025      
  0.10         0.20           25.0   0.74251    e       0.025              
  0.10         0.30           25.0   0.74505    e       0.025
  0.10         0.50           25.0   0.74840    e       0.025
  0.10         1.00           25.0   0.75237    e       0.025
  0.010        0.020          25.0   0.79501    e       0.025
  0.010        0.050          25.0   0.79628    e       0.025
  0.010        0.090          25.0   0.79899    e       0.025
  0.010        0.10           25.0   0.79947    e       0.025
  0.010        0.20           25.0   0.80353    e       0.025
  0.010        0.30           25.0   0.80619    e       0.025
  0.010        0.50           25.0   0.80897    e       0.025
  0.010        1.0            25.0   0.81404    e       0.025
  0.1333       0.06667        25.0   0.7313     f       0.15   
  0.1000       0.1000         25.0   0.7398     f       0.15
  0.0500       0.1500         25.0   0.7599     f       0.15    
  0.0200       0.1800         25.0   0.7854     f       0.15
  0.3333       0.1667         25.0   0.7087     f       0.15
  0.2500       0.2500         25.0   0.7184     f       0.15
  0.1250       0.3750         25.0   0.7406     f       0.15
  0.0500       0.4500         25.0   0.7673     f       0.15
  0.6667       0.3333         25.0   0.6900     f       0.15
  0.5000       0.5000         25.0   0.7006     f       0.15
  0.2500       0.7500         25.0   0.7250     f       0.15
  0.1000       0.9000         25.0   0.7532     f       0.15
  1.3333       0.6667         25.0   0.6670     f       0.15
  1.0000       1.0000         25.0   0.6797     f       0.15
  0.5000       1.5000         25.0   0.7078     f       0.15
  0.1500       1.3500         25.0   0.7439     f       0.15
  1.3333       0.6667         25.0   0.6504     f       0.15

Notes and References

Prefix m denotes molality; t - experimental temperature (^oC); E - electromotive force (V, or international volts, see below); ref. - source of data; weight - the weight given to the data point in the fit of the model (normalised).
Sources: d - A. K. Covington, J. V. Dobson and Lord Wynne-Jones (1965) Trans. Faraday Soc. 61, 2057-2062; e - H. S. Harned and R. D. Sturgis (1925) J. Am. Chem. Soc. 47, 945-953; f - M. Randall and C. T. Langford (1927) J. Am. Chem. Soc. 49, 1445-1450.
Data from Harned and Sturges, and Randall and Langford, are listed above in international volts and can be converted to V by multiplying by a factor of 1.000330. Standard emfs (E⁰) for the cells are as follows: d - 0.61123 V, e - 0.61212 V; f - 0.61252 V.

(4) Osmotic Coefficients from Electrodynamic Balance Measurements

   mH2SO4      mNa2SO4      osm       aW      t   ref.   weight  
  13.45600     13.45600    0.6817   0.371   25.0   g      0.0   
  13.13050     13.13050    0.6836   0.379   25.0   g      0.0   
  12.89050     12.89050    0.6925   0.381   25.0   g      0.0   
  12.52400     12.52400    0.6899   0.393   25.0   g      0.0   
  12.11500     12.11500    0.7016   0.399   25.0   g      0.0   
  11.91100     11.91100    0.7078   0.402   25.0   g      0.0   
  11.77200     11.77200    0.7123   0.404   25.0   g      0.0   
  11.63550     11.63550    0.7109   0.409   25.0   g      0.0   
  11.50300     11.50300    0.7151   0.411   25.0   g      0.0   
  11.19250     11.19250    0.7190   0.419   25.0   g      0.0   
  10.98350     10.98350    0.7207   0.425   25.0   g      0.0   
  10.76550     10.76550    0.7193   0.433   25.0   g      0.0   
  10.61950     10.61950    0.7192   0.438   25.0   g      0.0   
  10.40050     10.40050    0.7323   0.439   25.0   g      0.0   
  10.49350     10.49350    0.7198   0.442   25.0   g      0.0   
  10.01650     10.01650    0.7375   0.450   25.0   g      0.0   
  10.01650     10.01650    0.7293   0.454   25.0   g      0.0   
   9.64650      9.64650    0.7426   0.461   25.0   g      0.0   
   9.44000      9.44000    0.7483   0.466   25.0   g      0.0   
   9.39000      9.39000    0.7481   0.468   25.0   g      0.0   
   9.24250      9.24250    0.7494   0.473   25.0   g      0.0   
   9.14600      9.14600    0.7467   0.478   25.0   g      0.0   
   8.89250      8.89250    0.7528   0.485   25.0   g      0.0   
   8.71700      8.71700    0.7614   0.488   25.0   g      0.0   
   8.60000      8.60000    0.7696   0.489   25.0   g      0.0   
   8.46550      8.46550    0.7685   0.495   25.0   g      0.0   
   8.34550      8.34550    0.7706   0.499   25.0   g      0.0   
   8.21900      8.21900    0.7712   0.504   25.0   g      0.0   
   8.21000      8.21000    0.7676   0.506   25.0   g      0.0   
   8.05050      8.05050    0.7760   0.509   25.0   g      0.0   
   7.81850      7.81850    0.7761   0.519   25.0   g      0.0   
   7.71600      7.71600    0.7749   0.524   25.0   g      0.0   
   7.66550      7.66550    0.7731   0.527   25.0   g      0.0   
   7.55900      7.55900    0.7770   0.530   25.0   g      0.0   
   7.24800      7.24800    0.7889   0.539   25.0   g      1.0   
   7.10900      7.10900    0.7971   0.542   25.0   g      1.0   
   7.04550      7.04550    0.7922   0.547   25.0   g      1.0   
   6.92750      6.92750    0.7984   0.550   25.0   g      1.0   
   6.80050      6.80050    0.8010   0.555   25.0   g      1.0   
   6.69750      6.69750    0.7985   0.561   25.0   g      1.0   
   6.47600      6.47600    0.8055   0.569   25.0   g      1.0   
   6.45850      6.45850    0.8027   0.571   25.0   g      1.0   
   6.21900      6.21900    0.8103   0.580   25.0   g      1.0   
   6.23550      6.23550    0.8005   0.583   25.0   g      1.0   
   6.17550      6.17550    0.8006   0.586   25.0   g      1.0   
   6.04850      6.04850    0.8096   0.589   25.0   g      1.0   
   5.98200      5.98200    0.8056   0.594   25.0   g      1.0   
   5.98200      5.98200    0.8004   0.596   25.0   g      1.0   
   5.79050      5.79050    0.8135   0.601   25.0   g      1.0   
   5.68300      5.68300    0.8127   0.607   25.0   g      1.0   
   5.67850      5.67850    0.8053   0.610   25.0   g      1.0   
   5.57100      5.57100    0.8127   0.613   25.0   g      1.0   
   5.55300      5.55300    0.8126   0.614   25.0   g      1.0   
   5.52700      5.52700    0.8164   0.614   25.0   g      1.0   
   5.50150      5.50150    0.8175   0.615   25.0   g      1.0   
   5.48400      5.48400    0.8174   0.616   25.0   g      1.0   
   5.40450      5.40450    0.8266   0.617   25.0   g      1.0   
   5.45450      5.45450    0.8163   0.618   25.0   g      1.0   
   5.41700      5.41700    0.8164   0.620   25.0   g      1.0   
   5.36300      5.36300    0.8191   0.622   25.0   g      1.0   
   5.25950      5.25950    0.8183   0.628   25.0   g      1.0   
   5.16300      5.16300    0.8308   0.629   25.0   g      1.0   
   5.14050      5.14050    0.8258   0.632   25.0   g      1.0   
   5.10300      5.10300    0.8233   0.635   25.0   g      1.0   
   5.03050      5.03050    0.8265   0.638   25.0   g      1.0   
   4.96330      4.96330    0.8319   0.640   25.0   g      1.0   
   4.93200      4.93200    0.8284   0.643   25.0   g      1.0   
   4.87755      4.87755    0.8259   0.647   25.0   g      1.0   
   4.82415      4.82415    0.8320   0.648   25.0   g      1.0   
   4.60075      4.60075    0.8295   0.662   25.0   g      1.0   
   4.57080      4.57080    0.8318   0.663   25.0   g      1.0   
   4.51530      4.51530    0.8297   0.667   25.0   g      1.0   
   4.46660      4.46660    0.8357   0.668   25.0   g      1.0   
   4.40800      4.40800    0.8343   0.672   25.0   g      1.0   
   4.38080      4.38080    0.8363   0.673   25.0   g      1.0   
   4.38080      4.38080    0.8300   0.675   25.0   g      1.0   
   4.34565      4.34565    0.8304   0.677   25.0   g      1.0   
   4.29540      4.29540    0.8338   0.679   25.0   g      1.0   
   4.26940      4.26940    0.8357   0.680   25.0   g      1.0   
   4.23090      4.23090    0.8369   0.682   25.0   g      1.0   
   4.19075      4.19075    0.8352   0.685   25.0   g      1.0   
   4.17340      4.17340    0.8354   0.686   25.0   g      1.0   
   4.14395      4.14395    0.8349   0.688   25.0   g      1.0   
   4.10530      4.10530    0.8329   0.691   25.0   g      1.0   
   4.03260      4.03260    0.8380   0.694   25.0   g      1.0   
   4.01660      4.01660    0.8380   0.695   25.0   g      1.0   
   3.99835      3.99835    0.8352   0.697   25.0   g      1.0   
   3.93800      3.93800    0.8346   0.701   25.0   g      1.0   
   3.90970      3.90970    0.8406   0.701   25.0   g      1.0   
   3.88380      3.88380    0.8394   0.703   25.0   g      1.0   
   3.88380      3.88380    0.8327   0.705   25.0   g      1.0   
   3.82695      3.82695    0.8348   0.708   25.0   g      1.0   
   3.75160      3.75160    0.8376   0.712   25.0   g      1.0   
   3.71800      3.71800    0.8348   0.715   25.0   g      1.0   
   3.70050      3.70050    0.8317   0.717   25.0   g      1.0   
   3.75765      3.75765    0.8363   0.712   25.0   g      1.0   
   3.74965      3.74965    0.8381   0.712   25.0   g      1.0   
   3.76965      3.76965    0.8405   0.710   25.0   g      1.0   
   3.78795      3.78795    0.8399   0.709   25.0   g      1.0   
   3.79610      3.79610    0.8416   0.708   25.0   g      1.0   
   3.82275      3.82275    0.8391   0.707   25.0   g      1.0   
   3.85000      3.85000    0.8366   0.706   25.0   g      1.0   
   3.85620      3.85620    0.8386   0.705   25.0   g      1.0   
   3.87320      3.87320    0.8417   0.703   25.0   g      1.0   
   3.89465      3.89465    0.8405   0.702   25.0   g      1.0   
   3.93150      3.93150    0.8393   0.700   25.0   g      1.0   
   3.98695      3.98695    0.8376   0.697   25.0   g      1.0   
   4.00290      4.00290    0.8376   0.696   25.0   g      1.0   
   4.04645      4.04645    0.8384   0.693   25.0   g      1.0   
   4.06520      4.06520    0.8379   0.692   25.0   g      1.0   
   4.08865      4.08865    0.8429   0.689   25.0   g      1.0   
   4.10780      4.10780    0.8422   0.688   25.0   g      1.0   
   4.17575      4.17575    0.8350   0.686   25.0   g      1.0   
   4.19330      4.19330    0.8347   0.685   25.0   g      1.0   
   4.28230      4.28230    0.8332   0.680   25.0   g      1.0   
   4.29005      4.29005    0.8349   0.679   25.0   g      1.0   
   4.32435      4.32435    0.8345   0.677   25.0   g      1.0   
   4.33225      4.33225    0.8362   0.676   25.0   g      1.0   
   4.37535      4.37535    0.8373   0.673   25.0   g      1.0   
   4.41085      4.41085    0.8368   0.671   25.0   g      1.0   
   4.54435      4.54435    0.8367   0.663   25.0   g      1.0   
   4.59170      4.59170    0.8372   0.660   25.0   g      1.0   
   4.72080      4.72080    0.8322   0.654   25.0   g      1.0   
   4.74945      4.74945    0.8331   0.652   25.0   g      1.0   
   4.82750      4.82750    0.8315   0.648   25.0   g      1.0   
   4.89100      4.89100    0.8353   0.643   25.0   g      1.0   
   4.97735      4.97735    0.8324   0.639   25.0   g      1.0   
   5.08150      5.08150    0.8325   0.633   25.0   g      1.0   
   5.10300      5.10300    0.8319   0.632   25.0   g      1.0   
   5.17850      5.17850    0.8283   0.629   25.0   g      1.0   
   5.19350      5.19350    0.8287   0.628   25.0   g      1.0   
   5.25150      5.25150    0.8252   0.626   25.0   g      1.0   
   5.26300      5.26300    0.8290   0.624   25.0   g      1.0   
   5.29850      5.29850    0.8262   0.623   25.0   g      1.0   
   5.36750      5.36750    0.8212   0.621   25.0   g      1.0   
   5.41700      5.41700    0.8192   0.619   25.0   g      1.0   
   5.44600      5.44600    0.8286   0.614   25.0   g      1.0   
   5.54450      5.54450    0.8248   0.610   25.0   g      1.0   
   5.61050      5.61050    0.8205   0.608   25.0   g      1.0   
   5.70150      5.70150    0.8154   0.605   25.0   g      1.0   
   5.83350      5.83350    0.8181   0.597   25.0   g      1.0   
   5.91650      5.91650    0.8145   0.594   25.0   g      1.0   
   6.05900      6.05900    0.8134   0.587   25.0   g      1.0   
   6.21900      6.21900    0.8001   0.584   25.0   g      1.0   
   6.30800      6.30800    0.7989   0.580   25.0   g      1.0   
   6.34200      6.34200    0.8022   0.577   25.0   g      1.0   
   6.46450      6.46450    0.7969   0.573   25.0   g      1.0   
   6.55450      6.55450    0.7959   0.569   25.0   g      1.0   
   6.67850      6.67850    0.7958   0.563   25.0   g      1.0   
   6.86700      6.86700    0.7932   0.555   25.0   g      1.0   
   7.11650      7.11650    0.7819   0.548   25.0   g      1.0   
   7.21100      7.21100    0.7787   0.545   25.0   g      1.0   
   7.44700      7.44700    0.7770   0.535   25.0   g      1.0   
   7.57500      7.57500    0.7754   0.530   25.0   g      0.0   
   7.72400      7.72400    0.7718   0.525   25.0   g      0.0   
   7.86200      7.86200    0.7740   0.518   25.0   g      0.0   
   8.04150      8.04150    0.7634   0.515   25.0   g      0.0   
   8.09650      8.09650    0.7672   0.511   25.0   g      0.0   
   8.28700      8.28700    0.7539   0.509   25.0   g      0.0   
   8.34550      8.34550    0.7618   0.503   25.0   g      0.0   
   8.51700      8.51700    0.7638   0.495   25.0   g      0.0   
   8.93750      8.93750    0.7554   0.482   25.0   g      0.0   
   9.19400      9.19400    0.7386   0.480   25.0   g      0.0   
   9.17000      9.17000    0.7447   0.478   25.0   g      0.0   
   9.44000      9.44000    0.7358   0.472   25.0   g      0.0   
   9.49100      9.49100    0.7380   0.469   25.0   g      0.0   
   9.78050      9.78050    0.7284   0.463   25.0   g      0.0   
   9.83550      9.83550    0.7304   0.460   25.0   g      0.0   
  10.0595      10.0595     0.7303   0.452   25.0   g      0.0   
  10.3545      10.3545     0.7234   0.445   25.0   g      0.0   
  10.4315      10.4315     0.7241   0.442   25.0   g      0.0   
  10.7170      10.7170     0.7226   0.433   25.0   g      0.0   
  10.9330      10.9330     0.7122   0.431   25.0   g      0.0   
  11.0010      11.0010     0.7176   0.426   25.0   g      0.0   
  11.3915      11.3915     0.7065   0.419   25.0   g      0.0   
  11.6550      11.6550     0.7039   0.412   25.0   g      0.0   
  11.6935      11.6935     0.7054   0.410   25.0   g      0.0   
  12.0330      12.0330     0.6949   0.405   25.0   g      0.0   
  12.2200      12.2200     0.6994   0.397   25.0   g      0.0   
  12.6140      12.6140     0.6850   0.393   25.0   g      0.0   
  12.5240      12.5240     0.6918   0.392   25.0   g      0.0   
  12.7505      12.7505     0.6869   0.388   25.0   g      0.0   
  13.1550      13.1550     0.6823   0.379   25.0   g      0.0   
  13.4820      13.4820     0.6767   0.373   25.0   g      0.0   
  14.0175      14.0175     0.6706   0.362   25.0   g      0.0   
  14.3600      14.3600     0.6600   0.359   25.0   g      0.0   
  15.3945      15.3945     0.6572   0.335   25.0   g      0.0   
  15.5300      15.5300     0.6533   0.334   25.0   g      0.0   
  16.2445      16.2445     0.6471   0.321   25.0   g      0.0   
  16.5115      16.5115     0.6455   0.316   25.0   g      0.0   
  16.8665      16.8665     0.6406   0.311   25.0   g      0.0   
  17.7585      17.7585     0.6360   0.295   25.0   g      0.0   
  18.2170      18.2170     0.6269   0.291   25.0   g      0.0   
  18.6990      18.6990     0.6263   0.282   25.0   g      0.0   
  18.7995      18.7995     0.6264   0.280   25.0   g      0.0   
  20.4335      20.4335     0.6064   0.262   25.0   g      0.0   
  21.1050      21.1050     0.6077   0.250   25.0   g      0.0   
  22.4495      22.4495     0.5916   0.238   25.0   g      0.0   
  23.4175      23.4175     0.5875   0.226   25.0   g      0.0   
  23.7335      23.7335     0.5849   0.223   25.0   g      0.0   
  24.8195      24.8195     0.5800   0.211   25.0   g      0.0   
  25.7230      25.7230     0.5613   0.210   25.0   g      0.0   
  28.0785      28.0785     0.5507   0.188   25.0   g      0.0   
  29.2415      29.2415     0.5390   0.182   25.0   g      0.0   
  30.5085      30.5085     0.5268   0.176   25.0   g      0.0   
  36.8895      36.8895     0.4913   0.141   25.0   g      0.0   
  37.4755      37.4755     0.4907   0.137   25.0   g      0.0   
  38.2910      38.2910     0.4929   0.130   25.0   g      0.0   
  40.9610      40.9610     0.4733   0.123   25.0   g      0.0   
  41.1980      41.1980     0.4780   0.119   25.0   g      0.0   
  41.1980      41.1980     0.4857   0.115   25.0   g      0.0   
  40.4890      40.4890     0.5002   0.112   25.0   g      0.0   
  42.4390      42.4390     0.4812   0.110   25.0   g      0.0   
  42.4390      42.4390     0.4872   0.107   25.0   g      0.0   
  42.4390      42.4390     0.4892   0.106   25.0   g      0.0   
  43.7550      43.7550     0.4869   0.100   25.0   g      0.0   
  46.6480      46.6480     0.4689   0.094   25.0   g      0.0   
  48.9080      48.9080     0.4513   0.092   25.0   g      0.0   
  49.9485      49.9485     0.4502   0.088   25.0   g      0.0   
  53.7550      53.7550     0.4284   0.083   25.0   g      0.0

Notes and References

Prefix m denotes molality; t - experimental temperature (^oC); osm - stoichiometric osmotic coefficient; aW - the relative humidity in the electrodynamic balance chamber (equivalent to the solution water activity); ref. - the source of the data; weight - the weight given to the data point in the fit of the model (normalised).
Source: g - I. N. Tang and H. R. Munkelwitz (1994) J. Geophys. Res. 99, 18801-18808.

Model III: Data for Aqueous H+ - Na+ - SO42−

The System

Weights

The Data

(1) Solubilities of Solid Phases

(2) Osmotic Coefficients from Isopiestic Measurements

(3) Electromotive Force Measurements

(4) Osmotic Coefficients from Electrodynamic Balance Measurements

Model III: Data for Aqueous H⁺ - Na⁺ - SO₄²⁻