Octadecafluorooctane with Water (IUPAC SDS Volume 68)
Evaluator
Ari L. Horvath Imperial Chemical Industries (ICI) Limited
Evaluation
The solubility of octadecafluorooctane (1) in water (2) has been studied by four work groups in the same laboratory; whereas, the solubility of water (2) in octadecafluorooctane (1) has not been investigated yet.

It is probably safe to assume the data of Markina et al.1 and of Markina et al.2 have been superseded by those of Kabalnov et al.3 and of Kabal'nov et al.,4 since all four sets of measurements were made in the same laboratory.

The two sets of data, the earlier works of Markina et al.1,2 and the later measurements by Kabalnov et al.3,4 differ substantially by a factor of 5848. However, comparison of the trends in the solubility of perfluorohydrocarbons in water (see Preface) definitely indicate the lower value of Kabalnov et al.,3,4 should be preferred. Furthermore, because it is not possible to say which of the two3,4 is more accurate, it is suggested that the average of the two, which is recorded in Table 39 in weight percent, mole fraction, and mole per 100 gram, is probably the most reliable.
Table 39. Tentative solubility of octadecafluoroctane (1) in water (2)
C $T$ (°C) C $T$ ($\pu{K}$) D 100w1 D $x_{1}$ D $mol_{1}/\pu{100 g}$ (mol/g)
25.0 298.15 1.71 x 10-7 7.06 x 10-11 3.90 x 10-10

Sources:

1 Markina, Z. N.; Zadymova, N. M.; Shchukin, E. D.; Makarov, K. N.; Gervits, L. L.; Kolloidnyi Zh. 49, 1084-9 (1987).
2 Markina, Z. N.; Zadymova, N. M.; Shchukin, E. D.; Makarov, K. N.; Gervits, L. L.; Zh. Vses. Khim. OVa. im. D. I. Mendeleeva 33, 344-6 (1988).
3 Kabal'nov, A. S.; Makarov, K. N.; Shcherbakova, O. V.; J. Fluorine Chem. 50, 271-84 (1990).
4 Kabal'nov, A. S.; Gervits, L. D.; Makarov, K. N.; Kolloidnyi Zh. 52, 1060-6 (1990).