Objective

To measure the solubility of benzoic acid (Chemspider), in toluene (Chemspider). For a justification of this project see here.

Procedure

Saturated solutions are made of benzoic acid (Chemspider), in toluene (Chemspider), by charging a one dram vial with 700μl of the solvent. The solute is then added in subsequent amounts until the solution has reached a clear point of visible saturation. Each vial is vortexed for 30 seconds. After the process of vortexing is complete, each vial is centrifuged for one minute [at what multiple of g? Given the residual solute apparent on the sides of the vial in p1.jpg, I might be concerned about insufficient clearance of the supernatant --BH]. 300μl of the mother liquor is then pipetted into pre-weighed half-dram vials. The solution is weighed and entered into the speedvac, noting the pressure,. The solution is then re-weighed after all of the liquid has evaporated off. The results can be found on the following Spreadsheet. (use a different spreadsheet for each experiment JCB)

Add a discussion and conclusion - you have enough info to wrap up this experiment. Make sure to compare your results to what others in our group and in the literature have found. Also add your results to the SolubilitySum spreadsheet under the "list of experiements" JCB


Log


2008-11-6

14:42 Filled two dram vials with 700μl of toluene.
14:45 Saturated both vials, containing toluene solvent, with benzoic acid; vortexing for 30 seconds in between additions of solute to check for saturation.
14:54 Centrifuged both vials for one minute.
14:57 EXP009_p1.jpg.
15:02 Pipetted 300μl equivalents of the solution into two pre-weighed half-dram vials.
15:12 EXP009_p2.jpg.
15:15 Weighed both half-dram vials containing solution (weighed vials without screw cap).
15:19 Placed both half-dram vials into the speed vac for 25 minutes (There was observable pressure in the speed vac,I was unable to lift the top of the speed vac once the pump was turned on, however the pressure gauge was not working and therefore I was unable to note the pressure. Tim ran an assay before hand and was able to note a pressure of 5T).
15:49 Weighed both half-dram vials after the speed vac process.
15:52 EXP009_p3.jpg, EXP009_p4.jpg.


Tags


Compound
Inchi Key
Inchi
Benzoic acid
WPYMKLBDIGXBTP-UHFFFAOYAD
InChI=1/C7H6O2/c8-7(9)6-4-2-1-3-5-6/h1-5H,(H,8,9)
Toluene
YXFVVABEGXRONW-UHFFFAOYAT
InChI=1/C7H8/c1-7-5-3-2-4-6-7/h2-6H,1H3