So, I went to clean the downstem of my bong with the good ol alcohol and salt trick, keep in mind that I'm pretty sure the down stem didn't have any water in it and the only substances in the bag are alcohol, salt, and whatever crap was dislodged from my downstem. So, in my ziplock bag of alcohol and salt, a lot of the salt obviously sinks to the very bottom, then all of the particulates that can be seen with the naked eye seem to float in a middle later, of totally clear alcohol. Then on the top, is the rest of the alcohol which has no visible particulates but is bong-water green. Whenever I try and shake the bag to mix up the middle and upper layer, they always separate back into the layers. What confuses me is how is appears that the alcohol that's turned green has a totally different density than the alcohol that kept it's clear color, and that the heavy particulates will not float around in the green colored stuff, only the clear. It's like what happens when you put oil in water. I'll get a video up incase my description doesn't make sense. I just thought it was really fucking cool and I have no idea of the chemical process that's happening. My only guess would be that some of the THC that's been freed has congealed and created it's own area because THC is a lipid and won't mix with alcohol.
sounds like one layer is polar and the other is non-polar if my memory from chem serves me correctly. maybe some alcohol mixed with the gunk ,which may be nonpolar resulting in a nonpolar solution.
Might be the type of rubbing alcohol. Like Jay said, could be something weird with the polarity, but alcohol, water, and salt are all polar. The oils leftover in your downstem would be mostly be nonpolar.. So if you're using a 70% rubbing alcohol, that means you have 30% water in there. The oils probably mixed with the alcohol, creating a heavier nonpolar solution making the 30% water float on top. It'd probably be green because the only thing it'd be able to dissolve out of everything in your downstem would be the color.. As for the THC creating it's own area, THC is very much soluble in alcohol. While THC is a lipid of sorts, it's able to dissolve into other lipids (fats) and alcohol. http://forum.grasscity.com/incredible-edible-herb/373232-solubility-thc-chemistry-related.html Dude with post #4 explained it well.
^You're on the right track by bringing up the fact that there is a significant amount of water in the isopropyl alcohol. Isopropyl alcohol is normally miscible with water. But if you add a lot of salt to a mixture of iso + water, the water becomes highly polar which causes the isopropyl alcohol to separate into an aqueous and organic phase. It's called "salting out". And since isopropyl alcohol is less dense than water, it rises to the top just like oil on water. The chlorophyll and other chemicals in the mixture are soluble in the organic phase, and the particles floating in the aqueous phase aren't. Hence why the top layer of isopropyl alcohol is green, and the bottom layer of water is not.