Diffusion is the spreading of a substance and filling space available to it. In gases it is easy to see that it occupies the entire volume available to it. So it is a procession of movement of molecules from a high pressure region to low pressure region.
Diffusion in liquids is the transport of solvent molecules from low concentration to higher concentration of a solute.
Advantages of diffusion
1. Osmosis is also a process of diffusion, in which the solvent particles travel through a semipermeable membrane. This is used in filtering of water, using reverse osmosis.
2. Diffusion is good, as we light a stick of fragrance, it spreads through out the room. Same is the case with mosquito repellent sprays.
3. The gas in a LPG comes out due to diffusion, from high pressure to low pressure outside.
4. In our biological cell, the transfer of energy through ATP happens using diffusion process, to inside and to outside the cells. THis is due to concentration dependency.
5. Some mixtures can possibly be separated by this process.
6. Diffusion based detection is identified by methane detectors in underground mines. SMoke detectors in buildings are dependent on this process.
7. When a cell is cut inside body, then fluid/plasma transfer takes place based on concentration gradient.
1. When a poisonous snake or insect bites, the poison diffuses into the body.
and spreads, even if it is a slow process.
2. Dirty smells spread in air.
3. A small leak in a gas container or a liquid container causes leakage of the fluid.
4. Harmful greenhouse gases are rising to the ozone layer, due to pressure difference between the air at the surface of earth and at the ozone layer. They are degrading ozone layer.