Equilibrium constant (1 Viewer)

[Cab31]

I am having trouble figuring out what is meant by this in my experiement:

In determining equilibrium concentrations, we must not disturb the equilibrium in any way and this may be done by using a variety of methods. In this experiment, we make use of another parameter, the distribution coefficient of I2* which has a value of 115. If we place a chloroform layer in contact with aqueous layer containing a mixture of I2, I3 - and I-, the I2 will distribute itself between the aqueous and chloroform phases such that the concentration of I2 in the chloroform layer ([I2]CHCl3) and in the aqueous layer are related by:
[I2] CHCl3 = 115 + or - 1
[I2]

*(thats meant to be a little 2 by the way but i dont know how to put it up on the screen)

I am totally lost. Particuarly at the distribution coefficient part. I dont know what it means and i dont understand the purpose of the 115 thing. The experiment is all about finding the equilibrium constant of I2 +I- --> I3. I dont understand what this has to do with it!!! Are there any good chemists out there that can help me?!?
thanks guys!!

 

[currysauce]

...i don't think this sorta stuff is in the syllabus, i know The Acidic Environments dotpoints, i have never heard of this coefficient.

 

[Cab31]

sorry i thought i mentioned this but its first year uni. I am struggling with it and i was hoping one of the people that are good at chem would be able to help me.

 

[xiao1985]

um... i dont' quite know wut the whole q is abt, but the equilibrium constant of that particular eqn should mean that:

the concentration of I2 dissolved in CHCl3 over concentration of I2 in the aqueous (dissolved in water layer) has the equilibrium constant of 115.

so basically u ahve two layers... one chloroform, the other water... if u throw into the water certain amount of I2, conc of I2 dissovled in chloroform will be 115 times greater than that of water.

 

[Cab31]

Thanks heaps! That does actually help a lot~

 

[nit]

what course are you doing, cab31?

Edit: Don't worry about answering that...I found the answer in your profile.

 

[Cab31]

what course are you doing, cab31?

Edit: Don't worry about answering that...I found the answer in your profile.

yeah one of my subjects is 'chemistry for health proffessionals' this semester. It doesnt have anything to do with my actual degree, its just that my uni beleives that all health proffessionals should have a good background of chemistry. Other uni's that do my course dont have to do it....i was just lucky i guess! The problem is that i didnt expect to have to move to do this course (it was supposed to be offered in NSW but was then cancelled) and so i havent done chem before!! (strugglecity) lol!

 

[velox]

...i don't think this sorta stuff is in the syllabus, i know The Acidic Environments dotpoints, i have never heard of this coefficient.

It is in the syllabus, in Industrial Chem.