Researcher

Rida Atif

Objective

To determine the room temperature solubility of cinnamic acid in water, octanol, hexane, and cyclohexane

Procedure

Four large [[#|screw cap]] tubes were obtained (and labeled A through D) and all were filled with around 0.5g or 0.75g of trans-cinnamic acid. A sufficient (between 6-7mL) of water, 1-octanol, hexane, and cyclohexane were added into tubes A-D respectively. All tubes were attached to an apparatus that would shake them while keeping them submerged in a 25C water bath; the shake plate was turned to setting 3. The tubes were left to shake for about 120 hours. A 1mL volumetric flask was obtained and weighed empty. It was then filled with the pure solvent that was present in Tube A, water, and weighed again. The flask was cleaned, dried, and weighed empty once again. Lastly, the flask was filled with 1mL of the supernatant from Tube A and weighed one last time. This process was repeated for Tubes B, C, and D.

Results

Density Sheet
Tube A (cinnamic acid in water): 0.04M
Tube B (cinnamic acid in 1-octanol): 0.1337M
Tube C (cinnamic acid in hexane): 0.0457M
Tube D (cinnamic acid in cyclohexane): 0.1170M

Discussion

For Tube A, the value that was determined is 10 times too high from what the average reported values were for this solution at room temperature. It is possible that a chunk of cinnamic acid was sucked into the pipet because there was a layer of cinnamic acid on top of the supernatant.
For Tube B, the value that was determined is a lot lower than the reported values which are around 0.45M.
For Tube C, the value that was determined is very close to the only other reported value of 0.0395M; however, it was predicted that the solubility should be significantly higher. It has been noticed throughout this project in various experiments that cinnamic acid sticks to the glass walls when in hexane. It could be possible that it happened again in this temperature and the pipet only picked up almost pure hexane while the cinnamic acid that should have dissolved was stuck to the walls. This is thought because while observing the pipet with the supernatant inside, cinnamic acid crystals were left inside the walls of the pipet when the supernatant was pushed out.
For Tube D, the value that was determined is higher than the one reported value of 0.03M. However, the 0.03M value seems more accurate because the calculations of EXP309 make more sense with the use of the smaller value

Conclusion



Log

2012-08-08

11:56 - Four large screwcap tubes were obtained and labeled A through D
12:04 - Tube A was filled with 0.550g of cinnamic acid and 6.002g of water
12:17 - Tube B was filled with 0.777g of cinnamic acid and 6.751g of 1-octanol
12:24 - Tube C was filled with 0.515g of cinnamic acid and 5.219g of hexane
12:36 - Tube D was filled with 0.751g of cinnamic acid and 5.183g of cyclohexane
12:48 - All of the tubes were attached to an apparatus that would submerge them in a 25C water bath while shaking them on a shake plate. the shake plate was turned on to setting 3.

2012-08-13

12:23 - The shake plate was turned off and the tubes were removed
12:25 - A 1mL volumetric flask was cleaned and dried and weighed
12:26 - 1mL of water was measured into the flask and weighed
12;27 - The flask was dried out again and weighed
12:28 - The flask was filled with the supernatant from Tube A and weighed
12:48 - The process of weighing was repeated for Tube B
1:07 - The process of weighing was repeated for Tube C
1:24 - The process of weighing was repeated for Tube D