Diffusion refers to mixing two gases together. For example, the aroma of a meal when entering a room is the result of mixing two gases. That is, its dissemination.
All diffusion always occurs:
- From a higher concentration to a lower concentration point.
- It is a gradual process since the molecule undergoes several modifications in the diffusion with the other gaseous molecules.
- The speed of said diffusion will depend on the lightness or heaviness of each gas. Thus, there are heavy gases whose diffusion is slower and others (lighter gases) whose diffusion is faster.
The law of diffusion of Graham
If the conditions of pressure and temperature are equal, the speed of diffusion of the gases is inversely proportional to the square roots of their molar masses.
The effusion is the process by which a gas escapes to the outside of a container through a small opening or crack in it. Thus the effusion velocity is directly proportional to the speed of the molecules.
This means that, if a molecule of heavy gas presents an effusion, it will do so more slowly than a lighter gas molecule in which case the effusion will be faster. A deflated balloon is an example of effusion.
Examples of effusion
- Press the button of a deodorant
- Turn the knob of a burner to turn it on or off
- A helium container with a leak
- A hot air balloon that presents a loss
- The backpacks to propulsion
- The gas tubes of the astronauts
- A balloon deflating
- A flatulence
- The separation of uranium 238 in uranium 235
- A gas cylinder with a small leak through which it moves to another compartment or to the outside.
- When making coffee, the aroma is usually spread throughout the room.
- The perfume of flowers in a closed place
- A pleasant aroma or not that spreads throughout a room
- When a person perfumes and enters a room and everyone can smell their perfume
- The smoke released by cars in circulation
- Smoke from chimneys of homes or factories
- The smell of a decaying food inside the refrigerator
- The smell of an aromatic candle, incense or match
- The smoke of a cigarette in an airtight room
- Aromatic essences
- The smell of a rotten egg inside a container