[stann]

Hi,
I need to find the partition coefficient of Water in n-octane.
I've spend almost two days searching online and found various information about all sorts of solutes, but not for water itself.
This value should be well established, it seems.
Since water is insoluble in organic liquids, might it be unambiguously equal to zero?...
I'll be very grateful for references!...

Stann

[azmanam]

try these (subscription may be needed)

http://dx.doi.org/10.1016/j.chemosphere.2004.07.046
http://dx.doi.org/10.1021/je990190x

[stann]

try these (subscription may be needed)

http://dx.doi.org/10.1016/j.chemosphere.2004.07.046
http://dx.doi.org/10.1021/je990190x

Thank you, I've seen the first one. The question is whether Partition coefficient of n-octane in water is equal to the pratition coefficient of Water in n-octane. I'm not sure about that...

[alphahydroxy]

Not that I know really, but surely the partition coefficient for water must be zero, by definition...?

[Vidya]

What is partition coefficient?
It is the ratio of concentration of solute in two immiscible solvents.
water and octane forms two separate layers and used as two immiscible solvents for extraction and purification of compounds.
So we can say that their partition coefficient in each other is zero.

[stann]

What is partition coefficient?
It is the ratio of concentration of solute in two immiscible solvents.
water and octane forms two separate layers and used as two immiscible solvents for extraction and purification of compounds.
So we can say that their partition coefficient in each other is zero.

Not that I know really, but surely the partition coefficient for water must be zero, by definition...?

Yea, that's what I could expect. Apparently there is a study, mentioned above in this thread, which measures Part.Coeff. of n-octane in water at different temperatures. Thermodynamically mixing would never happened, however kinetically(including fluctuations) it's still possible:
"  The mole fraction aqueous solubility varies between (1.13–
1.60) · 10^(-7) for n-octane ...
"
The number is small, but it's not zero. Does complementarity work in this case? Is solubility(or part.coeff.) of water in n-octane is equal to solubility of n-octane in water?

[Borek]

Does complementarity work in this case? Is solubility(or part.coeff.) of water in n-octane is equal to solubility of n-octane in water?

I doubt.

Knowing concentration of water in water and water in n-octane one can easily calculate pertition coefficient. And it will be not zero.

A little bit artificial if you ask me.

[stann]

Does complementarity work in this case? Is solubility(or part.coeff.) of water in n-octane is equal to solubility of n-octane in water?

I doubt.

Knowing concentration of water in water and water in n-octane one can easily calculate pertition coefficient. And it will be not zero.

A little bit artificial if you ask me.

It should be easy i thought. But I can't find references to compare my part.coeff.(from simulations) with an experimental value.
... can it be found in some organic textbook?...
I'm not an expert in organic chemistry, so I don't know for sure. But I heard, that many physical and chemical properties of all sorts of chemicals are given in some organic books.

[soutoh65]

The number you need is 15 that is the closest.

It has a high number as would be expected because it is hydrophobic

kd= A1/C1

Rf = 1 + (pb/ne )K d