Diffusion Rate and Concentration

In summary, the rate of diffusion is influenced by the speed of molecules and the presence of a concentration gradient. However, it is also affected by the concentration of the particles themselves, as diffusion is dependent on mean free path and concentration is inversely proportional to mean free path. This means that the diffusion rate is inversely proportional to concentration. In real-world scenarios, the diffusion of a tracer in a medium may also be affected by the concentration of the tracer itself and its impact on the mean free path of other particles in the medium.
  • #1
Hereformore
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So the rate of diffusion is dependent upon the speed of the molecules and the existence of a concentration gradient.

What about the concentration of the particles themselves?

Diffusion is dependent upon mean free path and concentration is inversely proportional to mean free path. So does that mean that the diffusion rate is inversely proportional to concentration?

So if you had two compartments and two different scenarios:

Case 1: 10M separated from 1 MCase 2: 20M separated from 11M

Diffusion would be faster in the first case? This is confusing because apparently net flux here is the same according to my textbook since the difference is the same.
 
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Thanks for the post! Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
 
  • #3
Hereformore said:
So the rate of diffusion is dependent upon the speed of the molecules and the existence of a concentration gradient.

What about the concentration of the particles themselves?

Diffusion is dependent upon mean free path and concentration is inversely proportional to mean free path. So does that mean that the diffusion rate is inversely proportional to concentration?

Well, real-world diffusion problems usually consider the diffusion of a tracer in some other medium. So I suppose you would have to ask whether the concentrate of the tracer is significantly affecting the mean free path given all the other particles belonging to the (background) medium.

Just a thought, anyway.
 
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FAQ: Diffusion Rate and Concentration

What is diffusion rate?

Diffusion rate refers to the speed at which particles move from an area of high concentration to an area of low concentration. It is a measure of how quickly a substance can spread or disperse.

How does concentration affect diffusion rate?

The higher the concentration of a substance, the faster it will diffuse. This is because there are more particles in a given area, increasing the likelihood of collisions and therefore increasing the rate of diffusion.

What factors can affect diffusion rate?

The diffusion rate can be affected by temperature, molecular size, and the medium through which diffusion occurs. Higher temperatures generally lead to faster diffusion, smaller molecules diffuse faster than larger ones, and the medium's density and viscosity can also impact diffusion rate.

What is the relationship between diffusion rate and distance?

The diffusion rate is inversely proportional to the distance between two points. This means that the farther apart two points are, the slower the diffusion rate will be. This is because as distance increases, the particles have to travel a longer distance to reach the other side, resulting in a slower diffusion rate.

How can diffusion rate be measured or calculated?

Diffusion rate can be measured by observing the change in concentration over time or by using mathematical formulas such as Fick's law of diffusion. Fick's law takes into account factors such as concentration gradient, diffusion coefficient, and distance to calculate the rate of diffusion.

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