Researcher

Marshall Moritz

Objective

To determine the solubility of chloroacetic acid in 5 different solvents: methanol, acetonitrile, THF, DMSO, and toluene by NMR spectropscopy.

Procedure

Saturated solutions of chloroacetic acid in 5 different solvents were prepared by adding excess solute to 300uL of solvent in a half-dram vial. The vials were vortexed for approximately 10 seconds and if necessary, more solute was added until after vortexing, precipitate remained on the bottom of the vial. The vials were sonicated for 30 minutes and if necessary, more solute was added until solid remained for 30 minutes of consecutive sonication. The supernatant was then removed from the vials either by Pasteur pipette or by filtration. NMR tubes were labelled appropriately; M for methanol, A for acetonitrile, T for THF, D for DMSO, and O for toluene. 2-3 drops of the supernatant were added to 600uL of CDCl3 in the appropriate NMR tubes. An NMR of each sample was taken on the 500MHz Variac instrument.
Results Spreadsheet Exp095

Spectra

ONSCExp095A1 Raw Data for JCAMP dx file ONSCExp095A1
ONSCExp095A2 Raw Data for JCAMP dx file ONSCExp095A2
ONSCExp095D1 Raw Data for JCAMP dx file ONSCExp095D1
ONSCExp095D2 Raw Data for JCAMP dx file ONSCExp095D2
ONSCExp095D3 Raw Data for JCAMP dx file ONSCExp095D3
ONSCExp095M2 Raw Data for JCAMP dx file ONSCExp095M2
ONSCExp095M3 Raw Data for JCAMP dx file ONSCExp095M3
ONSCExp095O1 Raw Data for JCAMP dx file ONSCExp095O1
ONSCExp095O2 Raw Data for JCAMP dx file ONSCExp095O2
ONSCExp095O3 Raw Data for JCAMP dx file ONSCExp095O3
ONSCExp095T1 Raw Data for JCAMP dx file ONSCExp095T1
ONSCExp095T2 Raw Data for JCAMP dx file ONSCExp095T2
ONSCExp095T3 Raw Data for JCAMP dx file ONSCExp095T3

Discussion

The concentration of chloroacetic acid had not been previously reported at the time of experiment in any solute. Thus the values generated in this experiment could not be compared to any other values but themselves. There were no statistical anomalies in the solubilities of chloroacetic acid for any solvent [1]; the set of values for each solvent was fairly uniform. The solubility of chloroacetic acid in DMSO had a large range and a large standard deviation. Finding the solubility of chloroacetic acid in DMSO again would be useful for verifying the data. Interpretation of the NMR spectra was slightly complicated for the solubility in methanol. The methanol peaks on the spectra were fairly close to the solute peaks on the spectra and were thus slightly difficult to read. However, this was not a great obstacle as the upper and lower peak limits were still found. The experiment generated good results, and though this does not account for potential uniform experimental errors, the experiment was successful.

Conclusion

The solubility of chloroacetic acid in THF was found to be 9.81M, 9.52M, and 9.55M. The mean value was 9.63M and the standard deviation was 0.159.
The solubility of chloroacetic acid in toluene was found to be 1.20M, 1.67M, and 1.37M. The mean value was 1.41M and the standard deviation was 0.238.
The solubility of chloroacetic acid in methanol was found to be 9.52M and 9.38M. The mean value was 9.45M and the standard deviation was 0.098.
The solubility of chloroacetic acid in DMSO was found to be 11.22M, 11.92M, and 10.46M. The mean value was 11.20M and the standard deviation was 0.730.
The solubility of chloroacetic acid in acetonitrile was found to be 12.76M and 12.14M. The mean value was 12.45M and the standard deviation was 0.438.

Log

2009-05-20
9:24--Added 300uL of methanol to 3 vials labeled M1, M2, and M3.
9:26--Added 300uL of acetonitrile to 3 vials labeled A1, A2, and A3.
9:28--Added 300uL of THF to 3 vials labeled T1, T2, and T3.
9:30--Added 300uL of DMSO to 3 vials labeled D1, D2, and D3.
9:32--Added 300uL of toluene to 3 vials labeled O1, O2, and O3.
9:36--After adding 3 scoops of chloroacetic acid to vials A1, A2, and A3, the vials were capped and vortexed for approximately 10 seconds. This was repeated three times and the solution was found to be saturated.
9:46--After adding 3 scoops of chloroacetic acid to vials T1, T2, and T3, the vials were capped and vortexed for approximately 10 seconds. This was repeated twice and the solution was found to be saturated.
9:51--After adding 3 scoops of chloroacetic acid to vials M1, M2, and M3, the vials were capped and vortexed for approximately 10 seconds. This was repeated three times and the solution was found to be saturated.
9:56--After adding 3 scoops of chloroacetic acid to vials D1, D2, and D3, the vials were capped and vortexed for approximately 10 seconds. This was repeated three times and the solution was found to be saturated.
10:00--After adding 3 scoops of chloroacetic acid to vials O1, O2, and O3, the vials were capped and vortexed for approximately 10 seconds. This was repeated twice and the solution was found to be saturated.
10:29--All vials A1, A2, A3, O1, O2, O3, T1, T2, T3, D1, D2, D3, M1, M2, and M3 were set in a large beaker filled one-quarter with water and placed in the sonicator. The temperature was read at 26.0C and the timer was set to 30 minutes.
12:17--After adding two scoops of chloroacetic acid to vials A1, A2, A3, M1, M2, M3, D1, D2, and D3, the vials were capped and vortexed for approximately 10 seconds and the solution was again found to saturated. It appeared as though water leaked into vial T1, thus it was redone with 300uL of THF and chloroacetic acid until a saturated solution was created.
13:03--Vials T1, A1, A2, A3, M1, M2, M3, D1, D2, and D3 were set in a large beaker filled one-quarter with water and placed in the sonicator. The temperature was read at 23.5C and the timer was set to 30 minutes.

2009-05-21
9:20--Vials A1, A2, A3, M1, M2, M3, D1, an D2 were found to be no longer saturated. After adding one scoop of chloroacetic acid to these vials, the vials were capped and vortexed for approximately 10 seconds and the solution was again found to saturated.
9:38--Vials A1, A2, A3, M1, M2, M3, D1, an D2 were set in a large beaker filled one-quarter with water and placed in the sonicator. The temperature was read at 22.0C and the timer was set to 30 minutes.
9:47--Sonication was stopped after some vials were found to be no longer saturated. Two scoops of chloroacetic acid were added to all vials, and they were capped and vortexed for approximately 10 seconds until they were found to be saturated.
10:02--Vials A1, A2, A3, M1, M2, M3, D1, an D2 were set in a large beaker filled one-quarter with water and placed in the sonicator. The temperature was read at 24.0C and the timer was set to 30 minutes.
10:16--Sonication was stopped after some vials were found to be no longer saturated. Two scoops of chloroacetic acid were added to vials M1, M2, and A1, and these vials were were capped and vortexed for approximately 10 seconds until they were found to be saturated.
10:22--Vials A1, A2, A3, M1, M2, M3, D1, an D2 were set in a large beaker filled one-quarter with water and placed in the sonicator. The temperature was read at 24.0C and the timer was set to 30 minutes.
10:55--Vials A3, M1, M2 and M3 were filtered; the contents of the vial were passed through a pasteur pipette packed with cotton, thus filtering off the solids and yielding the supernatant. Vials A3 and M1 yielded no supernatant.
11:04--The saturated solutions from A1, A2, D1, D2, D3, O1, O2, O3, T1, T2, and T3 were collected by pasteur pipette as the supernatant was cleanly separated from the remaining precipitate.
11:26--NMR tubes were prepared for all vials; the saturated solutions collected from each vial were added to 600uL of CDCl3 in appropriately labelled NMR tubes.
12:30--NMR of all vials was taken on the 500MHz Variac instrument.

References

[1] Solubility of chloroacetic acid in non-aqueous solvents

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