Exp183

=Researcher= Jianbo Zhao =Objective= The objective of this expirement is to determine if the solubility of Cyclohexanecarboxylic in Hexanes varies with time in a heated water bath at 40C. In particular, the objective is to Observe whether the solution is saturated in room temperature(25C). =Procedure= 1. Set up all the equipments. Including temperature bath, tubes, balance and volumetric flasks 2. Take out 2 clean tubes label them as A1 and A2. 3. Started to put in some Cyclohexanecarboxylic. 4. Find two new empty tubes. Put each tube with Cyclohexanecarboxylic. Add up pure Hexane into both tubes. Until 3 quarters of the whole tube, stop. 5. Put on the cabs and seal the tube really tight. 6. After that, use a tape to take the two tubes together. Tape them on on the edge of temperature bath which they can stick with each other. Set the temperature into 42C and put them in.**[why 42C and not 40C? JCB]** 7. 60 minutes later, take tube both tubes out and transfer the liquid into new clean tubes marked as B1 and B2. 8. bath B1 in a beaker with 25C water about 10 minutes. 9. Take B1 out and observe whether there was solid coming out. =Results=


 * Pic.1 Measue each empty flasks with caps on.**


 * Pic.2 Measure the weight of acid.**


 * Pic.3 Bath both tubes with the temperature of 42C**


 * Pic.4 Bath the tube into 25C.**

=**Discussion**= As an observation experiement, no calculation spread sheet was shown. The whole point of the experiment is observation. During this calculation, we recorded the appearence of the tube. However, we did not observe any two layers of liquid. =Conclusion= Through the observation. I cannot see any solid came out from the tube. That means the solution was not saturated when the temperature is set up to 42C.

=Log=

Date: Oct, 4, 2010
16:04 Set up equipments, started the water bath 16:09 Start label two new tubes as 1 and 2. Weight each empty tubes. 16:12 Pick up cyclohexane and transfered them into both tubes. Take **picture 1**. 16:23 Take Hexanes out and pour them with a pipe into both tubes till 3/4 of the whole tube. 16:34 Seal and stick, then. Put both tubes into the water bath which has been set up as 21C. Take **picture 2**. 17:08 Clean and dry the flasks**.** 17:31 Take both out from water bath. Put 1 into a 24C water bath. Take **Picture 3**.**[SJK: These steps (17:31 and 17:47) don't match your procedure. There were supposed to be tubes A1 and A2 and then liquid transferred to tubes B1 and B2. It's really not clear what you did.]** 17:47 Take both of them out and find there are no crystal or layer of two different liquids.