Diffusion, Osmosis and Active Transport.

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Diffusion, Osmosis and Active transport. Diffusion: Seeing that substances have kinetic energy (energy of motion), they are continuously moving around, colliding with one another, and moving in various directions. The random mixing of ions and molecules due to their kinetic energy is called diffusion. If a particular ion or molecule is present in an area where there is a lot of that particular molecule, it would be in a high concentration area of itself. All the molecules would then collide with each other due to their kinetic energy, eventually forcing themselves away from each other, where there is more space. This area would be considered as a low concentration area because there would be less of these molecules. The difference in concentration between the two areas form a concentration gradient. The difference in diffusion between two different areas having different concentrations is called net diffusion. Substances undergoing net diffusion are said to move down or with their concentration gradient. After time (dependant on the substance) the substance will become evenly distributed. This is what’s known as equilibrium, although random kinetic motion continues, there’s no further net diffusion. Certain attributes can affect diffusion, such as heat, this will make diffusion occur more rapidly due to transferring more energy to the molecules to move around faster. Also a larger concentration gradient produces a faster diffusion, and smaller molecules diffuse more rapidly than larger molecules. If you imagine a crystal of dye in a beaker of water, the crystal would be the solute because it is the dissolvable substance, and the water is the solvent because it’s what the solute dissolves into and there tends to be more of it, both of these form together to create a solution. If you look at the colour of the water just next to the crystal it would be
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