Osmotic pressure: Quick Facts

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Photos

Two U-shaped tubes illustrate water diffusion across a semipermeable membrane. In diagram A, water moves from side 1 to side 2, driven by osmotic pressure and a concentration gradient, with impermeant substances unable to cross the membrane. In diagram B, hydrostatic pressure opposes the movement. Key concepts such as permeability, osmotic pressure, and impermeant membrane are labeled.

osmotic pressure

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Topics

isosmotic pressure hyperosmotic pressure hypoosmotic pressure osmometer semipermeable membrane Osmosis solution solvent colligative property pressure Atmospheric pressure radiation pressure high-pressure phenomena

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Key People

Jacobus Henricus van't Hoff, detail of an oil painting by Helene Büchmann.

Jacobus Henricus van ’t Hoff

Dutch chemist