MadSci Network: Earth Sciences |
Maegan- It is hard to say for sure what is going on without looking at your particular setup. The way this experiment is supposed to work is that the solution gets pulled up out of the glass in the small spaces in between the fibers of the string (this is called capillary action). Then, gravity makes the liquid flow to the middle of the X, which should be slightly lower than the rim of the glass. Solution accumulates there to the point where it begins to drip to form the stalactites and stalagmites (which in real life are formed by calcium carbonate not Epson salts). I suspect that the rim of the glass may pinch the capillaries in the yarn shut. This could cause the liquid to leak out in a very thin layer that would spread around the rim of the glass and evaporate, leaving the salt behind and never making it to the "X". You might want to try different types of string to see if that solves your problem. Alex
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