Researcher

Hai Truong - Ciana.

Objective


The goal is to determine solubility of salicylic acid in toluene at different temperatures.

Procedure

1. Weigh out 4 different masses of salicylic acid in crystal form.
2. Put them into small vials labeled from 1-4
3. Put each vial on a balance and use the glass pipette to deliver 500 mg of Toluene to each vial.
4. Used parafilm to seal all vials and put them into the bath and set to 80C [do not go above 40C JCB]-ok
5. Record the temperature that Salicylic acid dissolves in Toluene solvent.

Results

Spreadsheet-Exp142


Discussion

In this experiment, I forgot to pay attention to concentration and just picked random concentrations for salicylic acid and put in 500mg toluene. As the result, my lowest concentration in this experiment was 0.978M, and the salicylic acid in this concentration did not dissolve completely. In addition, I did not find out the solubility of the salicylic acid, so I cannot compare to previously reports. [Use the solubility search tool in the navigation bar to find the previous value JCB] I will do this experiment over on Friday Nov 06, 2009 to find out solubility of this acid in toluene.

Conclusion

Salicylic acid at the concentrations listed below did not dissolve in toluene even when the solutions were heated to 80C

concentration (M)
1.59
1.949
0.978
1.428


Log

2009-10-29
17:25 Labeled four small vials from 1-4.
17:30 Weighed out the masses of salicylic acid, data as in the chart above.
17:40 Put vials one-by-one on the balance. Tared it, and used the glass pipette to pour drop-by-drop toluene solvent into vials approximately 500ml. Data is in the chart above.
17:50 parafilmed the vials to seal them from leaking while in the hot water/glycol bath.
17:59 Placed vials into a bath at 23C and adjusted it to 40C.
18:15 Vortexed all 4 vials. [note bath temp JCB] ok
18:30 Adjusted the temperature to 80C, at this time, the real temperature is 40C.
19:15 The temperature reached 70C. Vortexed all vials again.
19:30 The temperature reached 80C. The temperature was too hot that parafilms of vials 1 and 4 were melt.
19:45 Took the vials 2 and 3 out of the hot bath. There are still many crystals in both vials, so salicylic acid is not dissolved at this concentration and 80C.