Fowarded message from Wolfgang Schechinger
----- Original Message -----
From: "Wolfgang Schechinger" <Wolfgang.Schechinger at med.uni-tuebingen.de>
To: "Mitchell Isaacs" <misaacs at student.usyd.edu.au>
Sent: Thursday, 13 April 2000 10:03
Subject: Re: Searching for a dependency of the maximum gas saturation in
> Given an unlimited amount of time (means we are looking at
> thermodynamic, not kinetical properties):
>> 1) I would look at the gas like it was a undissociated chemical, e.g.
> glucose.
>> 2) If the amount of substance causing the viscosity is vanishingly
> low, the solubility of the gas actually should not be different.
>> 3) If there is a significant amount of substance causing the
> viscosity (say 5%) and this substance is inert, I would assume the
> solubility as much as 95% of the solvent's capacity. Since there is
> 95% of the solvent in this case. Best would be considering molarities
> in this case.
>> 4) However, if the substance is changing the solvent's structure,
> the solute is intercalating or there is sme kind of a chemical
> reaction (like iodine in starch containing solutions or if KI is
> present), the solubility of the gas would be totally different and
> only a complex model (or practical measurements) would make a good
> approach
>> Just some ideas,
>> Wolfgang
>>> > It is my understanding that a solution can theoretically dissolve
> > the same amount of gas regardless of viscosity (if that is the only
> > variable).
> >
> > However, as can be learnt from vulcanology, viscosity may affect the
> > apparent solubility. Granitic, or high silica magmas are very
> > viscous, and have a much higher gas content (4-6%) than basaltic
> > magmas which are lower in silica (~1% gas).
> >
> > This is due largely to the viscosity, and the fact that the viscous
> > magmas do not release the gas nearly as readily.
> >
> > I would assume that the opposite effect can also be noticed, in that
> > gases will dissolve slower in a viscous solution, possibly to the
> > extent that the same concentration may not be reached in a practical
> > time frame.
> >
> > Cheers,
> > Mitchell
> >
> >
> > "Klemens Raithel" <klemens at biophysik.biologie.uni-mainz.de> wrote in
> > message news:38F498A7.B43FBAD5 at biophysik.biologie.uni-mainz.de... >
> > > > Uncle Al wrote: > > > Klemens Raithel wrote: > > > > > > I was
> > wondering, if there exists a dependency between the maximum > > >
> > saturation of a gas (oxygen) and the viscosity of the solution
> > caused by > > > a high concentrated cosolvent (e.g. sucrose, 3M). >
> > > > > > > Is there something known about this problem in the world
> > of science? > > > > It's hard to see how thermodynamics depends on
> > viscosity rather than > > concentration and identity of the solute.
> > A very small concentration > > of high MW polyacrylamide will give
> > you a very viscous aqueous > > solution. It's still mostly water. >
> > > Hi Uncle Al, > > I am not searching for a viscous solution mostly
> > consisting of water. > I am trying to find a relationship between
> > different viscous solutions and > their capacity to solve gas (to
> > the maximum saturation). > Does a physical formula or chemical rule
> > exist for THIS problem??? > Thanks, > > Klemens Raithel >
> >
> >
> -----
> This message is encrypted. Use your brain to decode it.
> -----
> Dr. Wolfgang Schechinger, Dept. of Pathobiochemistry
> University of Tuebingen, Germany
> email: wolfgang.schechinger at med.uni-tuebingen.de> wwWait: http://www.medizin.uni-tuebingen.de/~wgschech/start.htm> -----
> usual disclaimers apply
> -----