# Why doesn't Fick's Law account for temperature? watch

1. Temperature affects the speed of particles, that's pretty obvious.
So why doesn't ficks law,

Diffusion = (Surface Area x Concentration Gradient)/Diffusion distance.

include temperature?

Am I missing something, or is it one of those cases where I've just been taught something without being given the why.
2. (Original post by PKMN TRN JAM)
Temperature affects the speed of particles, that's pretty obvious.
So why doesn't ficks law,

Diffusion = (Surface Area x Concentration Gradient)/Diffusion distance.

include temperature?

Am I missing something, or is it one of those cases where I've just been taught something without being given the why.
There should be a constant in your equation.
Diffusion = K x (Surface Area x Concentration Gradient)/Diffusion distance.
This equation is not actually Fick's Law, just a representation of it.
Fick's Law is actually a partial differential equation, the answer is that the diffusion flux IS dependent on temperature, as the temperature affects the kinetic energy of the particles.
3. It's most certainly simplified into a form to get the principles across. You're not being asked to calculate based on a realistic model at this point as long as you can see that rate changes in certain ways with those variables then that's all you need at the time
4. I hate being lied to. Starting As chemistry was bad enough, being taught that all of GCSE was a lie, I can understand that though.
But why lie at As and A2? it's infuriating.
5. (Original post by PKMN TRN JAM)
I hate being lied to. Starting As chemistry was bad enough, being taught that all of GCSE was a lie, I can understand that though.
But why lie at As and A2? it's infuriating.
Because the reality is rather complicated, it's annoying yes, but at least its a better lie.
You do know that the rate of diffusion depends on temperature, you're just not expected to factor this into your calculations.

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