The passage of liquid through a semi-permeable partition (e.g. clay or parchment paper or cell walls in living organisms) that separates two liquids of different concentrations. Osmosis also plays a major role in metabolism. The Danish chemist Jacobus Hoff (1852-1911) discovered the phenomenon in 1874. This separating wall (also called diaphragm) is only permeable to the molecules of a liquid (e.g. water), but not to the dissolved substance (e.g. sugar molecules), due to an appropriate pore size. Diffusion (flowing apart) takes place towards the concentrated solution. If you place a container-1 (with a semi-permeable outer wall) with a highly concentrated solution (e.g. sugar water) in a container-2 with pure water in such a way that there is an equal level of liquid in both containers, the water molecules will migrate towards container-1.
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Dominik Trick
Technischer Lehrer, staatl. geprüfter Sommelier, Hotelfachschule Heidelberg