Diffusion

Diffusion is the process where particles move from an area of high concentration to an area of lower concentration, spreading out evenly in the available space.

If you spray perfume in one corner of a room, after a while, you can smell it in the entire room. This is because the perfume particles move from an area of high concentration (near the spray) to areas of lower concentration (other parts of the room).

Rate of Diffusion

The rate of diffusion is the speed at which particles move from areas of high concentration to areas of low concentration. It depends on several factors, including the nature of the particles, the temperature, and the concentration gradient.

Example: Imagine releasing both helium gas and sulfur hexafluoride gas in a room simultaneously. The helium, being lighter, will spread out faster than the sulfur hexafluoride. This shows that lighter gasses have a higher rate of diffusion.

Diffusion:

Diffusion is the process by which particles move from an area of high concentration to an area of low concentration. For instance, when you spray perfume, it spreads throughout the room — that’s diffusion!

Diffusion is the process by which particles move from an area of high concentration to an area of low concentration. The speed at which this happens is known as the rate of diffusion, and it can vary greatly depending on the particles involved.

In the case of gasses, lighter gasses tend to diffuse faster than heavier ones. For example, if you had a room filled with helium (a light gas) and sulfur hexafluoride (a much heavier gas), the helium would diffuse through the room much more quickly. This can be observed in real-world situations such as a helium balloon floating up into the sky, while the air around it (which contains heavier gasses like nitrogen and oxygen) remains grounded.

Fick’s Law of Diffusion

Fick’s law mathematically describes the process of diffusion. It states that the rate of diffusion is proportional to the concentration difference and the area over which diffusion occurs, and inversely proportional to the distance between the areas.

Example: If you have a semi-permeable membrane separating two solutions, one of high concentration and one of low concentration, the rate of diffusion of the solute will be higher if the membrane’s area is larger (more area for particles to move through), the concentration difference is greater (more “pressure” for particles to move), and the distance is smaller (less space to traverse).

Fick’s law of diffusion is a mathematical model that describes how diffusion occurs. It can be simplified as:

Rate of Diffusion ∝ Area × Concentration Difference / Distance

Where:

• The rate of diffusion is directly proportional to the area over which diffusion is taking place and the difference in concentration between the two areas.
• The rate of diffusion is inversely proportional to the distance between the two areas.

Simply put, diffusion happens more quickly when the area is larger, the concentration difference is greater, and the distance is smaller.