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 (3 ion) system are listed in Table 13 of Clegg et al. (1998b). Fits of the model are described in section 3.15 of that paper. The following types of data were considered:

Solubilities of the solids NH4NO3(s), NaNO3(s), and 2NaNO3.NH4NO3(s) in the ternary solutions.
Osmotic coefficients from isopiestic measurements.
Water activities from electrodynamic balance measurements (not fitted).
Equilibrium vapour pressures of water over solutions simultaneously saturated with respect to both salts (not fitted).

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

   mNaNO3   mNH4NO3      t    solid    ref.       weight
   9.0952    0.0000    0.00     2    a(2164)        -                                   
   7.7585   13.1713    0.00     2    a(2164)        -                                   
   7.7585   13.1713    0.00    12    a(2164)        -     
   0.0000   14.7906    0.00    12    a(2164)        -     
   9.8701    0.0000   15.00     2    a(2164)        -     
   9.5494    2.9990   15.00     2    a(2164)        -     
   9.3323    5.3475   15.00     2    a(2164)        -     
   9.1794    8.0682   15.00     2    a(2164)        -     
   8.9185   13.8544   15.00     2    a(2164)        -     
   8.8587   18.9811   15.00     2    a(2164)        -     
   8.8639   19.3945   15.00    12    a(2164)        -     
   7.1442   19.4938   15.00    12    a(2164)        -     
   4.2925   19.8564   15.00    12    a(2164)        -     
   3.2706   19.9857   15.00    12    a(2164)        -     
   2.0745   20.2697   15.00    12    a(2164)        -     
   0.0000   20.9112   15.00    12    a(2164)        -     
  11.3085    0.0000   30.00     2    a(2164)        -     
  10.3843   27.5772   30.00     2    a(2164)        -     
  10.3843   27.5772   30.00    12    a(2164)        -          
   0.0000   29.0541   30.00    12    a(2164)        -          
  621.21    1826.52  140.00     2    a(2165)        -          
  621.21    1826.52  140.00    14    a(2165)        -          
  275.83    1082.75  117.00     2    a(2165)        -          
  275.83    1082.75  117.00    13    a(2165)        -          
  39.2180  154.0838   95.00     2    a(2165)        -          
  39.2180  154.0838   95.00    13    a(2165)        -          
  15.4325   52.2446   60.00     2    a(2165)        -          
  15.4325   52.2446   60.00    11    a(2165)        -          
  11.4918   33.4123   40.00     2    a(2165)        -     
  11.4918   33.4123   40.00    11    a(2165)        -                              
   8.8633   19.7394   16.10     2    a(2165)        -          
   8.8633   19.7394   16.10    12    a(2165)        -          
   7.7051   13.2741    0.20     2    a(2165)        -          
   7.7051   13.2741    0.20    12    a(2165)        -          
   7.7957    9.7747  -15.40     2    a(2165)        -          
   7.7957    9.7747  -15.40    12    a(2165)        -          
  39.0486  153.5719  100.00     2    a(2166)        -          
  39.0486  153.5719  100.00    13    a(2166)        -          
   8.0423   18.7797   12.67    12    a(2167)        -          
   8.0462   21.9837   18.48    12    a(2167)        -     
   8.7003   17.4812    9.95     2    a(2167)        -     
   9.0168   17.4803   13.15     2    a(2167)        -     
   0.0000   14.7846    0.00    12    a(2168)        -     
   0.5383   14.4170    0.00    12    a(2168)        -     
   1.1031   13.8961    0.00    12    a(2168)        -     
   1.9300   14.0004    0.00    12    a(2168)        -     
   6.1006   13.3864    0.00    12    a(2168)        -     
   7.9046   13.1919    0.00    12    a(2168)        -     
   7.9046   13.1919    0.00     2    a(2168)        -     
   8.6394    0.0000    0.00     2    a(2168)        -     
   0.0000   22.2103   20.00    12    a(2169)        -     
   0.9212   22.4908   20.00    12    a(2169)        -     
   1.8788   23.1534   20.00    12    a(2169)        -     
   4.5971   21.2444   20.00    12    a(2169)        -     
   6.1929   20.8581   20.00    12    a(2169)        -     
   9.4123   22.1310   20.00    12    a(2169)        -     
   9.4123   22.1310   20.00     2    a(2169)        -     
   9.8245   11.5386   20.00     2    a(2169)        -     
   9.8981    6.8132   20.00     2    a(2169)        -     
  10.1945    2.8674   20.00     2    a(2169)        -     
  10.3500    0.0000   20.00     2    a(2169)        -     
   0.0000   36.7899   40.00    11    a(2169)        -     
   1.3062   37.4901   40.00    11    a(2169)        -     
  13.9766   41.1217   40.00    11    a(2169)        -     
  13.9766   41.1217   40.00     2    a(2169)        -     
  13.2665   18.8330   40.00     2    a(2169)        -     
  12.5972    3.8690   40.00     2    a(2169)        -     
  12.3935    0.0000   40.00     2    a(2169)        -     
   0.0000   51.2805   60.00    11    a(2169)        -     
   1.3755   51.2512   60.00    11    a(2169)        -     
   4.5333   52.7619   60.00    11    a(2169)        -     
   6.1844   53.7444   60.00    11    a(2169)        -     
  15.8798   53.5462   60.00    11    a(2169)        -     
  15.8798   53.5462   60.00     2    a(2169)        -     
  14.7213    0.0000   60.00     2    a(2169)        -     
   0.0000   79.6401   80.00    11    a(2169)        -     
   9.2201   89.8642   80.00    11    a(2169)        -     
  19.0493  101.3270   80.00    11    a(2169)        -     
  26.0626  103.5979   80.00    11    a(2169)        -     
  26.0626  103.5979   80.00     2    a(2169)        -     
  22.6987   58.4097   80.00     2    a(2169)        -     
  18.9609   15.2765   80.00     2    a(2169)        -     
  16.1590    3.6013   80.00     2    a(2169)        -     
  17.5747    0.0000   80.00     2    a(2169)        -     
   0.0000  128.6738   90.00    13    a(2169)        -     
   3.9265  133.3167   90.00    13    a(2169)        -     
   8.1886  140.4323   90.00    13    a(2169)        -     
  12.5094  157.9482   90.00    13    a(2169)        -     
  18.1435  187.4212   90.00    13    a(2169)        -     
  65.9792  297.1807   90.00    13    a(2169)        -     
  65.9792  297.1807   90.00     2    a(2169)        -     
  20.0674    0.0000   90.00     2    a(2169)        -     
  10.5556    0.0000   25.00     2    a(2170)      0.2     
  10.8582    3.1125   25.00     2    a(2170)      0.2     
  10.1654    6.8894   25.00     2    a(2170)      0.2     
  10.4521   10.1736   25.00     2    a(2170)      0.0     
  10.2904   13.4330   25.00     2    a(2170)      0.0     
   9.6679   17.1553   25.00     2    a(2170)      0.2     
  12.8214   21.8141   25.00     3    a(2171)      0.0  
  10.6358   21.1366   25.00     3    a(2171)      0.0  
   9.5539   20.0593   25.00     3    a(2171)      0.0  
   8.4891   19.3736   25.00     3    a(2171)      0.0     
   8.0426   19.5952   25.00     3    a(2171)      0.0     
   9.1204   23.2687   25.00    12    a(2171)      1.0     
   4.6380   26.2036   25.00    12    a(2171)      0.0     
   4.9339   22.5685   25.00    12    a(2171)      0.0     
   0.0000   25.4572   25.00    12    a(2171)      1.0     
   0.0000   23.1601   20.00    12    a(2172)        -     
   3.5109   21.1374   20.00    12    a(2172)        -     
   7.6607   20.9219   20.00    12    a(2172)        -     
   8.5248   20.6221   20.00    12    a(2172)        -     
   8.5248   20.6221   20.00     2    a(2172)        -     
   9.8957    0.0000   20.00     2    a(2172)        -     
   9.4685    3.1902   20.00     2    a(2172)        -     
   9.1331    6.3775   20.00     2    a(2172)        -     
   8.4593   17.1376   20.00     2    a(2172)        -     
   6.3729    6.7672  -24.20     0       b           -     
   6.3729    6.7672  -24.20    12       b           -     
   6.3729    6.7672  -24.20     3       b           -     
   6.3533    5.7469  -23.00     2       b           -     
   6.3533    5.7469  -23.00     0       b           -     
   6.3533    5.7469  -23.00     3       b           -     
   6.5363    8.3289  -14.50    12       b           -     
   6.5363    8.3289  -14.50     3       b           -     
   6.5363    8.3289  -14.50    97       b           -     
   6.9122   11.4001   -3.10    12       b           -     
   6.9122   11.4001   -3.10     3       b           -     
   6.9122   11.4001   -3.10    98       b           -     
   8.4319   20.1975  -18.20     3       b           -     
   8.4319   20.1975  -18.20    98       b           -     
   8.4319   20.1975  -18.20    99       b           -     
  10.5598    0.0000   25.00     2       b         0.2      
   9.6055    1.9680   25.00     2       b         0.0     
   9.0014    3.9220   25.00     2       b         0.0     
   9.0491    5.4464   25.00     2       b         0.0     
   9.3048    7.6581   25.00     2       b         0.0     
   9.6702   11.4664   25.00     3       b         0.2       
   9.2963   12.6403   25.00     3       b         0.2       
   9.3206   18.1721   25.00     3       b         0.2       
   9.5774   21.1728   25.00     3       b         0.2     
   9.0890   22.3314   25.00     3       b         0.2     
   9.0890   22.3314   25.00    12       b         0.0     
   8.6091   23.7786   25.00    12       b         1.0     
   6.9468   24.0124   25.00    12       b         1.0     
   3.8076   24.8047   25.00    12       b         1.0     
   0.0000   24.8001   25.00    12       b         1.0     
   0.4131    2.1931   -7.10     0       c           -      
   0.8205    2.1937   -8.00     0       c           -      
   1.5206    2.2018   -9.50     0       c           -      
   2.2150    2.1987  -11.10     0       c           -      
   2.9162    2.2068  -12.60     0       c           -     
   3.3321    2.2068  -13.60     0       c           -     
   4.1557    2.1968  -15.30     0       c           -     
   5.5526    2.2265  -18.40     0       c           -     
   7.6217    2.2114   -9.60     2       c           -     
   8.3089    2.2116   -1.70     2       c           -     
   9.0011    2.2076    6.70     2       c           -     
   9.6947    2.1988   14.40     2       c           -     
  10.3613    2.2107   22.40     2       c           -     
  11.2147    2.1797   30.80     2       c           -     
   1.6834    5.3627  -15.10     0       c           -     
   3.3500    5.3788  -18.40     0       c           -     
   5.0611    5.3975  -21.80     0       c           -     
   5.8941    5.4130  -23.40     0       c           -     
   7.5513    5.3543   -9.20     2       c           -     
   8.3895    5.3504    2.50     2       c           -     
   9.2405    5.3345   11.50     2       c           -     
  10.0731    5.3339   20.50     2       c           -     
  10.9072    5.3207   29.50     2       c           -     
  12.0114   18.2829   40.00     2       c           -     
  10.1577   15.5196   25.20     2       c           -     
   9.2885   14.1737   16.20     2       c           -     
   8.6192   13.1545    7.50     2       c           -     
   8.1819   12.4933    2.60     2       c           -     
   7.7517   11.8101   -2.90     2       c           -     
   6.0417    9.2293  -12.90    15       c           -     
   5.4805    8.3822  -15.90    15       c           -     
   4.9300    7.5617  -19.20    15       c           -     
   7.3869   11.2914   -6.00    15       c           -     
   7.0246   10.7436   -7.40    15       c           -     
   6.7432   10.3062   -9.10    15       c           -     
   6.4026    9.7622  -11.40    15       c           -     
   4.3006    6.6016  -22.20     0       c           -     
   3.9005    5.9977  -20.00     0       c           -     
   2.4526    3.7744  -14.10     0       c           -     
   1.7939    2.7629  -11.10     0       c           -     
   1.1707    1.8025   -8.10     0       c           -     
   0.8612    1.3423   -6.20     0       c           -     
  11.0523   23.0936   31.00     2       c           -     
  10.4439   21.6822   28.20     2       c           -     
   9.6299   20.0663   21.60     2       c           -     
   9.1638   19.0079   14.50     2       c           -     
   4.4370    9.2641  -14.10    15       c           -     
   3.8522    8.0578  -19.20    15       c           -     
   8.5096   17.7578   11.30    15       c           -     
   8.0575   16.8091    9.80    15       c           -     
   7.4379   15.5089    6.30    15       c           -     
   6.8981   14.4101    2.90    15       c           -     
   6.1528   12.8439   -1.20    15       c           -     
   5.5300   11.5945   -5.70    15       c           -     
   5.0653   10.5866   -8.80    15       c           -     
   3.4115    7.1058  -20.80     0       c           -     
   2.8905    6.0521  -18.40     0       c           -     
   2.6189    5.4788  -17.40     0       c           -     
   1.8180    3.7881  -12.80     0       c           -     
   1.3618    2.8753  -10.50     0       c           -     
   0.9140    1.9410   -7.90     0       c           -     
   0.6921    1.4698   -6.20     0       c           -     
   0.5507    1.1837   -5.20     0       c           -     
  11.5074   30.0825   36.20     2       c           -     
  10.9215   28.6239   33.10     2       c           -     
  10.5117   27.5467   29.60     2       c           -     
   9.4123   24.6566   25.00    15       c         0.0     
   8.4039   22.1136   20.60    15       c           -     
   7.2289   18.9945   14.20    15       c           -     
   9.9983   26.2705   27.40    15       c           -     
   2.0477    4.4060  -14.20     0       c           -     
   2.0453    5.2603  -15.70     0       c           -     
   2.0393    6.1634  -17.00     0       c           -     
   2.0426    7.0275  -18.00     0       c           -     
   2.0425    7.9297  -19.40     0       c           -     
   2.0143    9.6738  -13.50    15       c           -     
   2.0551   12.6024   -4.00    15       c           -     
   2.0796   15.5485    4.10    15       c           -     
   2.0285   18.4914   11.20    15       c           -     
   1.8825   21.2029   17.10    15       c           -     
   2.0308    8.7898  -16.60    15       c           -     
   5.0372    1.0584  -14.80     0       c           -     
   5.0450    2.1389  -16.80     0       c           -     
   5.0310    3.1969  -18.50     0       c           -     
   5.0185    4.2897  -20.10     0       c           -     
   5.0205    5.3543  -21.70     0       c           -     
   5.0163    6.3919  -23.50     0       c           -     
   4.9671    8.8705  -15.50    15       c           -     
   4.9853   12.4630   -3.20    15       c           -     
   5.0052   16.7037    7.80    15       c           -     
   5.0524   19.6591   14.60    15       c           -     
   5.1425   23.4146   21.40    15       c           -     
   5.4104   27.3576   27.40    15       c           -     
   6.8355    2.2435  -21.50     0       c           -     
   6.8355    2.2435  -21.50     2       c           -     
   6.4430    5.4534  -24.70     0       c           -     
   6.4430    5.4534  -24.70     2       c           -     
   7.4925   11.5028   -5.40     2       c           -     
   7.4925   11.5028   -5.40    15       c           -     
   4.4659    6.8364  -23.00     0       c           -     
   4.4659    6.8364  -23.00    15       c           -     
   9.0355   18.7399   13.60     2       c           -     
   9.0355   18.7399   13.60    15       c           -     
   3.5906    7.6734  -22.00     0       c           -     
   3.5906    7.6734  -22.00    15       c           -     
  10.2473   27.0016   28.50     2       c           -     
  10.2473   27.0016   28.50    15       c           -     
   2.0359    8.1013  -19.60     0       c           -     
   2.0359    8.1013  -19.60    15       c           -     
   5.0323    6.9022  -23.80     0       c           -     
   5.0323    6.9022  -23.80    15       c           -     
  10.8604    0.0000   30.00     2       c           -     
  11.1646    2.2328   30.00     2       c           -     
  11.5707    4.3352   30.00     2       c           -     
  11.0667    5.4306   30.00     2       c           -     
  11.2675   10.3230   30.00     2       c           -     
  10.7027   16.4428   30.00     2       c           -     
  10.8560   18.7057   30.00     2       c           -     
  10.5587   22.0577   30.00     2       c           -     
   8.3457   21.8741   30.00    15       c           -     
   4.9242   22.1925   30.00    15       c           -     
   1.9966   23.2451   30.00    15       c           -     
   0.0000   23.4070   30.00    15       c           -     
  10.2349   27.4243   30.00     2       c           -     
  10.2349   27.4243   30.00    15       c           -     
  10.6747   28.5763   30.00     2       c           -     
  10.6747   28.5763   30.00    15       c           -     
   7.7529   28.2482   30.00    15       c           -     
   4.9931   27.9509   30.00    15       c           -     
   4.9169   28.9024   30.00    15       c           -     
   3.0744   29.0852   30.00    15       c           -     
   1.9820   30.1809   30.00    15       c           -     
   0.0000   29.8568   30.00    15       c           -     
   6.4674    5.9806  -26.40     0       d           -     
   6.4674    5.9806  -26.40     2       d           -     
   6.4674    5.9806  -26.40    15       d           -     
   9.0840   20.3550   16.00     2       d           -     
   9.0840   20.3550   16.00    15       d           -     
   8.0358   19.8010   20.00     2       d           -     
   8.0358   19.8010   20.00    15       d           -     
  65.2770  294.5000   98.00     2       d           -     
  65.2770  294.5000   98.00    15       d           -     
   0.000   36.693     40.0     15       e           -     
   4.726   35.878     40.0     15       e           -     
  11.651   35.782     40.0     15       e           -     
  11.651   35.782     40.0      2       e           -     
  11.677   22.075     40.0      2       e           -     
  11.868   11.222     40.0      2       e           -     
  12.355    5.699     40.0      2       e           -     
  12.344    0.000     40.0      2       e           -     
   0.000   29.714     30.0     15       e           -     
   1.405   28.654     30.0     15       e           -     
   4.236   28.439     30.0     15       e           -     
   8.222   28.950     30.0     15       e           -     
  10.714   29.293     30.0     15       e           -     
  10.714   29.293     30.0      2       e           -     
  10.498   24.410     30.0      2       e           -     
  10.376   10.811     30.0      2       e           -     
  10.189    7.688     30.0      2       e           -     
  10.746    3.859     30.0      2       e           -     
  10.860    0.000     30.0      2       e           -     
   0.000   15.147      1.0     15       e           -     
   2.697   15.114      1.0     15       e           -     
   5.219   14.756      1.0     15       e           -     
   7.954   14.253      1.0     15       e           -     
   7.954   14.253      1.0      2       e           -     
   8.107    7.884      1.0      2       e           -     
   8.568    3.751      1.0      2       e           -     
   8.696    0.000      1.0      2       e           -     
   4.007    7.991    -19.0     15       e           -     
   5.183    8.085    -19.0     15       e           -     
   6.924    7.794    -19.0     15       e           -     
   6.924    7.794    -19.0      2       e           -     
   6.950    5.315    -19.0      2       e           -     
   6.946    3.181    -19.0      2       e           -     
   7.463    0.829    -19.0      2       e           -     
   7.463    0.829    -19.0      0       e           -     
   6.169    3.467    -19.0      0       e           -     
   4.522    6.014    -19.0      0       e           -     
   3.521    6.990    -19.0      0       e           -     
   2.997    8.076    -19.0      0       e           -     
   2.997    8.076    -19.0     15       e           -     
   7.153    6.103    -25.0      2       e           -     
   7.153    6.103    -25.0     15       e           -     
   7.153    6.103    -25.0      0       e           -     
  11.309   21.150     25.0      2       f         0.0     
  11.309   21.150     25.0      3       f         0.0     
   8.865   23.590     25.0     15       f         1.0     
   8.865   23.590     25.0      3       f         0.2

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, 11 = NH4NO3(s) (alpha rhombic), 12 = NH4NO3(s) (beta rhombic), 13 = NH4NO3(s) (tetragonal), 14 = NH4NO3(s) (cubic), 15 = NH4NO3(s) (no crystal form given), 2 = NaNO3(s), 3 = 2NaNO3.NH4NO3(s). Solids for references a(2164), a(2165) and a(2166) were not identified. These have been estimated by comparison with other data. The double salt (3) has been entered above where Bergman and Shulyak (1972) indicate a composition of 2NH4NO3.NaNO3(s). This may be incorrect.
Sources: a - H. L. Silcock, Solubilities of Inorganic and Organic Compounds, Vol. 3, Pergamon, Oxford, 1979, (the table numbers are given in parentheses); b - Bergman and Shulyak (1972) Russ. J. Inorg. Chem. 17, 593-596; c - S. Y. Shpunt (1946) Zh. Prikl. Khim. 19, 293-303; d - D. Mazzotto (1891) Nuovo Cimento [3] 29, 21-36; e - H. Nakamura (1982) Kogyo Kagaku 43, 63-69; f - Yu. M. Timoshenko (1986) Russ. J. Inorg. Chem. 31, 1843-1844.

(2) Osmotic Coefficients from Isopiestic Measurements

  mNaNO3   mNH4NO3      t       osm    ref.      weight                                    
   9.670   0.000      25.0     0.7746   g         0.0     
   8.729   1.233      25.0     0.7519   g         1.0     
   8.178   1.957      25.0     0.7391   g         1.0      
   7.127   3.333      25.0     0.7161   g         1.0      
   6.291   4.422      25.0     0.6992   g         1.0      
   5.447   5.528      25.0     0.6825   g         1.0      
   4.405   6.885      25.0     0.6635   g         1.0      
   3.408   8.183      25.0     0.6462   g         1.0      
   2.247   9.694      25.0     0.6273   g         1.0      
   0.000  12.641      25.0     0.5926   g         0.0      
   7.667   0.000      25.0     0.7761   g         0.0      
   6.897   0.975      25.0     0.7559   g         1.0      
   6.447   1.543      25.0     0.7448   g         1.0      
   5.592   2.614      25.0     0.7251   g         1.0      
   4.918   3.457      25.0     0.7105   g         1.0      
   4.241   4.305      25.0     0.6963   g         1.0      
   3.413   5.334      25.0     0.6803   g         1.0      
   2.629   6.314      25.0     0.6654   g         1.0      
   1.724   7.438      25.0     0.6495   g         1.0      
   0.000   9.583      25.0     0.6210   g         0.0      
   6.397   0.000      25.0     0.7809   g         0.0      
   5.736   0.810      25.0     0.7631   g         1.0      
   5.351   1.281      25.0     0.7532   g         1.0      
   4.628   2.164      25.0     0.7355   g         1.0      
   4.058   2.853      25.0     0.7228   g         1.0      
   3.491   3.543      25.0     0.7102   g         1.0      
   2.801   4.377      25.0     0.6959   g         1.0      
   2.150   5.162      25.0     0.6832   g         1.0      
   1.404   6.057      25.0     0.6695   g         1.0      
   0.000   7.746      25.0     0.6449   g         0.0      
   5.427   0.000      25.0     0.7862   g         0.0      
   4.852   0.686      25.0     0.7705   g         1.0      
   4.520   1.082      25.0     0.7617   g         1.0      
   3.898   1.822      25.0     0.7460   g         1.0      
   3.410   2.398      25.0     0.7347   g         1.0      
   2.927   2.970      25.0     0.7236   g         1.0      
   2.342   3.659      25.0     0.7110   g         1.0      
   1.793   4.306      25.0     0.6996   g         1.0      
   1.168   5.039      25.0     0.6874   g         1.0      
   0.000   6.409      25.0     0.6658   g         0.0      
   4.728   0.000      25.0     0.7921   g         0.0      
   4.220   0.596      25.0     0.7776   g         1.0      
   3.926   0.940      25.0     0.7697   g         1.0      
   3.378   1.579      25.0     0.7555   g         1.0      
   2.952   2.075      25.0     0.7450   g         1.0      
   2.528   2.566      25.0     0.7352   g         1.0      
   2.019   3.154      25.0     0.7240   g         1.0      
   1.543   3.705      25.0     0.7136   g         1.0      
   1.003   4.326      25.0     0.7028   g         1.0      
   0.000   5.482      25.0     0.6832   g         0.0      
   4.186   0.000      25.0     0.7972   g         0.0      
   3.731   0.527      25.0     0.7837   g         1.0      
   3.465   0.829      25.0     0.7771   g         1.0      
   2.976   1.391      25.0     0.7641   g         1.0      
   2.597   1.826      25.0     0.7544   g         1.0      
   2.221   2.254      25.0     0.7457   g         1.0      
   1.770   2.767      25.0     0.7355   g         1.0      
   1.351   3.245      25.0     0.7260   g         1.0      
   0.877   3.782      25.0     0.7162   g         1.0      
   0.000   4.779      25.0     0.6982   g         0.0

Notes and References

Prefix m denotes molality; t - experimental temperature (^oC); osm - the molal osmotic coefficient; ref. - source of data; weight - the weight given to the data point in the fit of the model (normalised).
Sources: g - A. Kirgintsev and A. V. Lukyanov (1965) Russ. J. Phys. Chem. 39, 653-655.

(3) Water Activities from Electrodynamic Balance Measurements

  mNaNO3   mNH4NO3     t         aW    np  ref.  weight                                
   3.530   3.5300    23.9      0.8371  1    h     0.0     
   3.640   3.6400    23.9      0.8337  1    h     0.0     
   3.875   3.8750    23.9      0.8246  1    h     0.0     
   4.830   4.8300    23.9      0.7939  1    h     0.0     
   5.580   5.5800    23.9      0.7669  1    h     0.0     
   6.560   6.5600    23.9      0.7284  1    h     0.0                     
   7.625   7.6250    23.9      0.6905  1    h     0.0               
   8.445   8.4450    23.9      0.6575  1    h     0.0               
   9.720   9.7200    23.9      0.6209  1    h     0.0               
  10.780  10.7800    23.9      0.5924  1    h     0.0               
  11.995  11.9950    23.9      0.5568  1    h     0.0               
  12.880  12.8800    23.9      0.5371  1    h     0.0               
  14.510  14.5100    23.9      0.5132  1    h     0.0               
  15.280  15.2800    23.9      0.4878  1    h     0.0               
  16.010  16.0100    23.9      0.4749  1    h     0.0               
  17.900  17.9000    23.9      0.4514  1    h     0.0               
   4.065   4.0650    23.9      0.8140  2    h     0.0               
   4.305   4.3050    23.9      0.8071  2    h     0.0               
   5.005   5.0050    23.9      0.7892  2    h     0.0               
   6.425   6.4250    23.9      0.7469  2    h     0.0               
   7.140   7.1400    23.9      0.7208  2    h     0.0               
   7.990   7.9900    23.9      0.6885  2    h     0.0               
   8.935   8.9350    23.9      0.6544  2    h     0.0               
   9.925   9.9250    23.9      0.6253  2    h     0.0               
  10.890  10.8900    23.9      0.5903  2    h     0.0               
  11.730  11.7300    23.9      0.5664  2    h     0.0               
  12.340  12.3400    23.9      0.5484  2    h     0.0               
  12.995  12.9950    23.9      0.5259  2    h     0.0               
  14.030  14.0300    23.9      0.5062  2    h     0.0               
  14.545  14.5450    23.9      0.4853  2    h     0.0               
  15.665  15.6650    23.9      0.4637  2    h     0.0               
   5.4670  1.8225    23.8      0.8196  1    h     0.0               
   5.7825  1.9275    23.8      0.8112  1    h     0.0               
   6.6525  2.2175    23.8      0.7932  1    h     0.0               
   8.0400  2.6800    23.8      0.7593  1    h     0.0               
   9.1425  3.0475    23.8      0.7305  1    h     0.0               
   9.8625  3.2875    23.8      0.7080  1    h     0.0               
  11.3025  3.7675    23.8      0.6671  1    h     0.0               
  11.9775  3.9925    23.8      0.6444  1    h     0.0               
  13.1100  4.3700    23.8      0.6201  1    h     0.0               
  13.6650  4.5550    23.8      0.6001  1    h     0.0               
  14.6775  4.8925    23.8      0.5770  1    h     0.0               
  15.8175  5.2725    23.8      0.5511  1    h     0.0               
  16.5375  5.5125    23.8      0.5287  1    h     0.0               
  17.7675  5.9225    23.8      0.5080  1    h     0.0               
  17.9400  5.9800    23.8      0.4987  1    h     0.0               
  18.1425  6.0475    23.8      0.4875  1    h     0.0               
  19.0725  6.3575    23.8      0.4759  1    h     0.0               
  19.3275  6.4425    23.8      0.4689  1    h     0.0               
  19.8150  6.6050    23.8      0.4617  1    h     0.0               
  20.5350  6.8450    23.8      0.4517  1    h     0.0               
   5.2875  1.7625    23.8      0.8196  2    h     0.0               
   5.9925  1.9975    23.8      0.8031  2    h     0.0               
   7.6875  2.5625    23.8      0.7627  2    h     0.0               
   8.8500  2.9500    23.8      0.7342  2    h     0.0               
   9.6525  3.2175    23.8      0.7117  2    h     0.0               
  10.5900  3.5300    23.8      0.6862  2    h     0.0               
  11.5650  3.8550    23.8      0.6588  2    h     0.0               
  12.5100  4.1700    23.8      0.6338  2    h     0.0               
  13.3950  4.4650    23.8      0.6125  2    h     0.0               
  13.8900  4.6300    23.8      0.5980  2    h     0.0               
  14.8050  4.9350    23.8      0.5761  2    h     0.0               
  15.6375  5.2125    23.8      0.5572  2    h     0.0               
  16.4850  5.4950    23.8      0.5365  2    h     0.0               
  17.7000  5.9000    23.8      0.5102  2    h     0.0               
  18.3750  6.1250    23.8      0.4956  2    h     0.0               
  19.0800  6.3600    23.8      0.4818  2    h     0.0               
  19.4850  6.4950    23.8      0.4699  2    h     0.0               
  20.1525  6.7175    23.8      0.4594  2    h     0.0               
  21.0375  7.0125    23.8      0.4510  2    h     0.0

Notes and References

Prefix m denotes molality; np - particle number; aW - the water activity of the solutions (equivalent to the ambient relative humidity); ref. - source of data; weight - the weight given to the data point in the fit of the model (normalised).
These data were not fitted, but are included here for reference.
Sources: h - Z. Ha, L. Choy, and C. K. Chan (2000) J. Geophys. Res. 105, 11699-11709.

(4) Equilibrium Water Vapour Pressures

    t      pH2O      ref.    weight                                 
   15.0     7.0       i       0.0     
   17.5     8.0       i       0.0     
   20.0     9.1       i       0.0     
   22.5    10.4       i       0.0     
   25.0    11.7       i       0.0     
   27.5    13.3       i       0.0     
   30.0    15.0       i       0.0     
   32.5    16.8       i       0.0     
   35.0    18.7       i       0.0     
   37.5    21.0       i       0.0     
   40.0    23.1       i       0.0       
   42.5    25.6       i       0.0       
   45.0    28.2       i       0.0       
   47.5    31.1       i       0.0       
   50.0    34.0       i       0.0       
   52.5    37.0       i        -        
   55.0    40.3       i        -        
   57.5    43.7       i        -        
   60.0    47.2       i        -        
   10.0     5.4       j       0.0       
   15.0     7.0       j       0.0       
   20.0     9.0       j       0.0       
   25.0    11.6       j       0.0       
   30.0    14.6       j       0.0       
   35.0    18.5       j       0.0       
   38.0    21.4       j       0.0       
   30.0    14.75      k       0.0

Notes and References

t - temperature (^oC); pH2O - equilibrium water vapour pressure (mm Hg) above solutions saturated with respect to both NH4NO3(s) and NH4NO3(s); ref. - source of data; weight - the weight given to the data point in the fit of the model (normalised).
These data were not fitted, but are included here for reference.
Sources: i - P. Dingemans and L. L. Dijkgraaf (1948) Recl. Trav. Chim. 67, 225-230; j - E. B. R. Prideaux (1920) J. Chem. Soc. (Ind. Trans.) 39, 182T-185T; k - J. R. Adams and A. R. Merz (1929) Ind. Eng. Chem. 21, 305-307.

Model III: Data for Aqueous NH4+ - Na+ - NO3−

The System

Weights

The Data

(1) Solubilities of Solid Phases

(2) Osmotic Coefficients from Isopiestic Measurements

(3) Water Activities from Electrodynamic Balance Measurements

(4) Equilibrium Water Vapour Pressures

Model III: Data for Aqueous NH₄⁺ - Na⁺ - NO₃⁻