Can someone explain what happened to my osmosis experiment?
Starch is actually polar, it just doesn’t dissolve very easily unless it “unwinds”, and it has less tendency to open up in water. You could heat it up to unwind it, like when you make gravy. Hexane is *very* non-polar. No matter what you dissolve in it, water will not easily diffuse into it. This is why the potatoes didn’t change – the water just stayed in the potato, no matter how much salt or starch was in the hexane. Alcohols like ethanol or isopropanol (I’m not sure which you used) are actually very polar, hydrophillic (water-loving) solvents. If you used pure ethanol, then it contained *no* water to begin with. In osmosis, water flows from high concentrations (the potato) to low concentrations (the alcohol solvent), essentially “drying” out the potato. Even if you used 70% isopropanol (like you buy in a drug store), that’s 70% alcohol and 30% water (by volume), which means that it is still very “dry” compared to a potato, and will pull water out of the potato. It doesn’t matter wh
