what happens when a substance redistributes itself by diffusion

What happens is...
"More to Less".  If you have a tub of hypotonic solution, say sea water, and you submerge yourself, the sea water has more salt than water and your body has more water than salt.  So....salt sucks.  It will pull the pure water from your body in the attempt to create a balance of salt and water.  If you have a tub of hypertonic solution, say 100% pure water, and you submerge yourself, your body has more salt than water and the tub is 100% pure water.  So, remembering that SALT SUCKS, your body will absorb the tub water in the attempt to create a balance of water and salt.  It's always more to less and salt sucks.

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