The solubilities of the pharmacopœial organic acids and their salts / by Atherton Seidell.

  • Seidell, Atherton, 1878-1961.
Date:
[1910]
Catalogue details

Licence: In copyright

Credit: The solubilities of the pharmacopœial organic acids and their salts / by Atherton Seidell. Source: Wellcome Collection.

    56/104 (page 54)
    titration, separate into two layers when allowed to stand. These solutions which resulted in the titration numbers 1 to 6 (see p. 52), were transferred to graduated cylinders and allowed to stand 24 hours and the volumes of the upper and lower layers then read. The perfectly clear layers of which the upper was yellowish and the lower nearly white or ])ale straw colored in each case were then analyzed hy withdrawing enough to fill a j)ycnometer, weighing and titrating the dissolved oleic acid with alcoholic sodium hydroxide solution. An unsuccessful attempt was made in one case to determine the alcohol ])resent hy neutralizing the oleic acid with aqueous alkalf and distilling. The ex- cessive foaming, how- ever, prevented a suc- cessful distillation of the alcohol and the proced- ure was abandoned. The results which were ob- tained are as follows. The figures in paren- theses indicate estimated values. Some loss oc- curred in transferring the solutions from the titration flasks to the graduated cylinders, and therefore the sum of the volumes of the upper and lower layers are less than that of the solu- tions mixed as given for the titration results on page 52. This loss also accounts for the differences in the amounts of oleic acid found and those originally added. Fro. 4.—Curves showing the solubilities of camphoric, gallic, oleic, and stearic acids in aqueous alcohol solutions at 25°. Deter- mina- tion No. Ivower layer. Upper layer. Volume- of lower layer. Specific gravity. Oleic acid per 100 grams solution. Oleic acid in lower layer. Volume of upper layer. Specific gravity. Oleic acid per 100 grams solution. Oleic acid in upper layer. c.c. Ora ms. C.C. c. c. Grams. c. c. 1 29.0 0.893 5.123 1.48 1.0 (0.35) 2 26.0 0.890 7.347 1.89 6.0 (0.875) 33.83 1.98 .I 22.7 0.891 8. 572 1.93 9.3 (0.875) 31.39 2.78 4 16.0 t). 6.139 0.98 19.0 0.876' 35.54 6.59 5 6.0 (0.890) 6.259 0.37 33.2 0.878 36. 61 11.87 G 4. 5 (0.28) 55.5 0.877 44.59 24.14