A straightforward example of a process involving osmosis is when a dry sponge is placed in water, causing water to rush into it.
Osmosis is a specific type of diffusion that focuses solely on the movement of water molecules across a semi-permeable membrane. This movement occurs from an area of high water concentration (low solute concentration) to an area of low water concentration (high solute concentration), without requiring energy input (passive transport).
Here's a breakdown of how osmosis works with the sponge example:
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The dry sponge: Initially, the sponge has a very low water concentration compared to the surrounding water.
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The water: The pan of water represents an area of high water concentration.
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The process: Water molecules move from the pan (high concentration) into the sponge (low concentration) through the sponge's porous material, acting as a semi-permeable barrier. This continues until equilibrium is reached, meaning the water concentration inside and outside the sponge becomes relatively equal.
Another common example is the swelling of raisins placed in water. The water moves into the raisin, which has a higher sugar concentration, causing it to plump up. Similarly, plants rely on osmosis to absorb water from the soil into their roots.
Essentially, osmosis is the passive movement of water to equalize solute concentrations across a membrane.
