Jianbo Zhao


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


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.



Pic.1 Tubes with pure Piperonal.

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

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.



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.