Exp187

=Researcher= Jianbo Zhao =Objective= To determine the solubility of [|piperonal] in pure n-hexane using density measurement via different temperature. Volumetric flask size effect on percent error was also examined. [|assumption]

=Procedure=

1. Set up all the equipments. Including temperature bath, tubes, balance and volumetric flasks 2. Take out 6 clean tubes label them as from 1 to 6. 3. Started to measure the mass of Piperonal. With the calculation it would be around 3g 4. Put each tube with Piperonal. Add up pure n-Hexane into both tubes. Until 3 quarters of the whole tube, stop. 5. Put on the cabs and seal the tube really tight. 7. Make the bath temperature to -15C. Each tube test with 10C increases. -15C and -7C 8. Transfer solution out and measure mass via different volumes of flasks.

=Results=

[|Measurement]


 * Pic.1 Tubes with pure Piperonal.**


 * Pic.2 Solution 1 in -15C water bath.**

=Discussion= =Conclusion= =Log=
 * Pic.3 After bath for 1 hour.**
 * 1) The experiment is not perfectly set. Two temperature datas were measured.
 * 2) The temperature was not flexible during measurement. It continued changing.
 * 1) Two concentration were measured in temperature -15C and -7C.
 * 2) The temperature can decrease below -8.5C.

2010-11-03
16:03 Set up water bath down to -15C. 16:08 Measure mass of 6 clean empty tubes and marked them from 1 to 6. 16:14 Pour pure Piperonal into tubes, each of them around 3g. Weight them. Take Pic.1 16:25 Put Hexane into tubes. 16:33 Seal 6 tubes 16:40 Tape Tube 1 and put it into water bath at -15C and it wen throught to -15C**.** See crystal on the glass wall immidietely. Take Pic.2 17:38 Take tube 1 out and take Pic.3, see crystals on tube side. 17:40 Increase the bath temperature to -7C 17:45 Weight mass of 4 volume of flasks 10ml, 5ml, 2ml and 1ml. Pour in the solution quickly and weight the mass. 18:02 Put the typed Tube 2 into -7C water bath.