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Solubility book (3rd Edn)
To determine the solubility of
in n-hexane (1), ethyl acetate (2), isopropanol (3), dichloromethane (4), and benzene (5) to compare against the
predictions of the Abraham solubility model
The solubility of benzalaniline at 29C is:
in n-hexane: 1.469 M
in isopropanol: 1.431 M
[Report which solvents gave gels too. JCB]
The solubility for benzalaniline in n-hexane and isopropanol at 29C was determined, and compared to the
Abraham model's predictions
. Predictions of 1.203 M (hexane) and 0.725 M (isopropanol) were found to be relatively accurate when compared to experimentally determined solubilities. The difference between the predicted and experimental solubilities for hexane was 0.266 (18.12%) and for isopropanol was 0.706 (49.34%). It should also be noted that the solubilities were recorded at 29C, which would result in a higher solubility measurement. With this in mind, the predictions are even closer than the numbers suggest.
The solubilities of benzalaniline in n-hexane and isopropanol were measured at 29C to be 1.469 M and 1.431 M, respectively. These correlate well with abraham predictions. The remaining 3 measurements were not taken due to gelling.
12:22 - Mixed roughly 300mg of benzalaniline with 100 to 1000 microliters of each solvent. The sample in dichloromethane dissolved completely. Added more solid until it didn't dissolve completely.
12:48 - Added each sample to a 47C bath.
13:03 - Bath temperature is 51C, each sample is completely dissolved. Removed all samples from bath. Set on counter at RT (29C).
13:30 - 1 had precipitate, the rest did not.
13:36 - Blew air on samples 2-5 until precipitate formed.
14:09 - Samples 2, 4 and 5 made a gel. Attempted to break by stirring with a spatula, but no clear supernatant formed. Heated each sample for 30 seconds, clear solution formed.
14:15 - Blew air on samples 2, 4 and 5. The solid precipitated all at once, and no pure solution could be extracted from any of these 3 samples.
14:17 - Mixed supernatant from samples 1 and 3 with CDCl3
[I later found out that this CDCl3 had no TMS, and am having difficulty assigning a peak to a known ppm - EC]
. Added to NMR tube.
[That should not be an issue - you can look up the solvent peaks or the solute peaks and use that as a ref. Lets take a look: upload the spectra. JCB]
14:35 - Took HNMR of 1 and 3 using 500MHz varian NMR.
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