[224] The equilibria between calcium chloride and water have been most completely studied by Roozeboom (Zeitschr. physikal. Chem., 1889, 4. 31).
[225] Hammerl, Sitzungsber. Wien. Akad., 2te Abteil, 1878, 78. 59. Roozeboom, Zeitschr. physikal. Chem., 1889, 4. 31.
[226] Lidbury, Zeitschr. physikal. Chem., 1902, 39. 453. The curvature at the melting point is all the greater the more the compound is dissociated into its components in the liquid state. If the compound is completely undissociated, even in the vapour phase, the two branches of the curve will intersect, (e.g. pyridine and methyl iodide; Aten, Versl. Konink. Akad. Wetensch. Amsterdam, 1905, 13. 462). The smaller the degree of dissociation, therefore, the sharper will be the bend. (See Stortenbeker, Zeitschr. physikal. Chem., 1892, 10. 194.) From the extent of flattening of the curve, it is also possible, with some degree of approximation, to calculate the degree of dissociation of the substance in the fused state. (See Roozeboom and Aten, Zeitschr. physikal. Chem., 1905, 53. 463; Kremann, Zeitschr. Elektrochem., 1906, 12. 259.)
[227] See Roozeboom, Zeitschr. physikal. Chem., 1889, 4. 31.
[228] Tammann, Wied. Annalen, 1899, 68. 577.
[229] Duhem, Journ. Physical Chem., 1898, 2. 31.
[230] Gibbs, Trans. Conn. Acad., 3. 155; Saurel, Journ. Phys. Chem., 1901, 5. 35.
[231] In the case of the fusion of a compound of two components with formation of a liquid phase of the same composition, the temperature is a maximum; in the case of liquid mixtures of constant boiling-point, the temperature may be a minimum (p. [105]).
[232] Roozeboom, Zeitschr. physikal. Chem., 1892, 10. 477. The formula of ferric chloride has been doubled, in order to avoid fractions in the expression of the water of crystallization.
[233] Roozeboom, Zeitschr. physikal. Chem., 1892, 10. 477.