Diffusion is the spontaneous spreading of matter (particles or molecules), heat, momentum, or light. Diffusion is one type of transport phenomenon. Diffusion is the movement of particles from higher chemical potential to lower chemical potential (chemical potential can in most cases of diffusion be represented by a change in concentration). It is readily observed, for example, when dried food like spaghetti is cooked; water molecules diffuse into the spaghetti strings, making them thicker and more flexible. It is a physical process rather than a chemical reaction, which requires no net energy expenditure. In cell biology, diffusion is often described as a form of passive transport, by which substances cross membranes.
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Diffusion
Diffusion is the spontaneous spreading of matter (particles or molecules), heat, momentum, or light. Diffusion is one type of transport phenomenon. Diffusion is the movement of particles from higher chemical potential to lower chemical potential (chemical potential can in most cases of diffusion be represented by a change in concentration). It is readily observed, for example, when dried food like spaghetti is cooked; water molecules diffuse into the spaghetti strings, making them thicker and more flexible. It is a physical process rather than a chemical reaction, which requires no net energy expenditure. In cell biology, diffusion is often described as a form of passive transport, by which substances cross membranes.
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