2009.14 . Rock Salt & Ice Water
Helping students learn about freezing point depression this week in chemistry lab. Kind of a lame photo, but the salt crystals flying around the bottom in the vortex created by the stirring bar looked kind of neat, so I tried the macro setting on the Lumix camera and got these results. Probably would have been better with the D70 and f/1.8 lens, but .. ehh, I do what I can. It's the end of the day. I just got home. And this is today's best photo on my camera. Time for bed. :)
The experiment here actually involved determining the freezing point and freezing point depression constant of cyclohexane, then using those data to determine the molar mass of an unknown solute. The students would lower a test tube containing a small stirring bar and a digital thermometer into the ice water, then watch for the temperature to level off and crystals to form when the freezing process begins. These students decided just to play around with the vortexes for a while between experiment trials.