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    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.
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    (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.
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    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
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    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.
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    (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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