[AdiDex]

When i was reading text from a book i came to read a fact
" the collison are not so effective in heterogeneous system as in homogenous systems "
I tried to proof it mathematically
I assumed i have container who have 10 molecules of x and 10 molecules of y ...
Let the volume of container be 10 units..
Now i seperated the container into two equal parts (say A and B) by a imaginary line...
X and Y following first order of kinetics.

Case 1 : Homogeneous system
5 molecules of each x and y are in A as in B

So the average rate  =  k/2 ( [X]_A[Y]_A + [X]_B[Y]_B )

(I divided the whole equation by 2 because i am measuring the average reaction.....reactions in two different containers are going on independently..)

Rate = k/2 ( (5/5)(5/5) + (5/5)(5/5) )
          = k

Case 2 - heterogenous system

Say in A , 6 X and 4 Y and
         In B,  6  Y and 4 X
Rate = k/2 ( (6/5)(4/5) + (4/5)(6/5) )
          = 0.96k

Case 3 : heterogeneous system

In A , 6 X , 6 Y
In B , 4 X , 4 Y

Average rate = k/2 ( (6/5)(6/5) + (4/5)(4/5) )
                        = 1.04k

So what is the problem with case 3 .?
It is opposing the fact..!!!

[mjc123]

That's not what is meant by "heterogeneous". A heterogeneous reaction is one where the reagents are not all in one phase, such as the reaction between a solid and a species in solution or in the gas phase, or a reaction at the interface between two immiscible solutions. A homogeneous reaction takes place within a single phase, e.g between species in solution or gas. Heterogeneous reactions are limited by only being able to occur at an interface, whereas homogeneous reactions take place throughout the volume of the phase.

[AdiDex]

Hmmm thanks..

By the way.... In my third case there is a mistake..
I got my mistake..
In third case in A there are 12 molecules where as in B , there are 8 molecule....
The scenario will be different from it...in both of the partition i should place equal no. Of particles...
Because it has greater probability..(entropy favoured) otherwise the pressure will be different..

I got your point...that what does actually heterogenous means..!
I'm just telling my view.

Thanks