Me and my friend are building a diffusion cloud chamber for a school project. In stead of using dry ice or a peltier, we have used the phase changer of a freezer to cool our plate. We were able to cool our plate down to -35.8° C. The top of our chamber was heated to 9.6° C, and the distance between the top and bottom of our chamber measures approximately 15 cm. We provided our chamber with 99% pure isopropanol, but unfortunately no trails showed up. We did not even saw cloud formation or precipitation, just pools of isopropanol forming on the bottom.
At first, we thought the temperature was not low enough to supersaturate the air with isopropanol. We decided to test this by polluting the air in the chamber with charcoal. The charcoal-dustparticles would act as seeds for vapor to condense around just like ionised tracks were supposed to do. To our surprise, we found that charcoal did cause cloud formation and precipitation. Can we now conclude that our chamber was indeed in a supersaturated state, and that the temperature is not the problem?
If temperature is in fact the limiting factor, obviously we have to try to lower it further. However, might it be an idea to cool the air quicker by decreasing the height whilst maintaining the temperature gradient? Or might there be an other way (besides pressure) to quickly decrease the vapor capacity of air?
Apologies for the length of my question(s). Any input is much appreciated!
Edit: To clarify my question, does the air have to be supersaturated for clouds to form around dust particles? In order to see ion-tracks, the air does have to supersaturated. However, dust particles are way bigger, so is it right to pull the conclusion that the chamber is supersaturated when clouds form around dust particles?
