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Rf factors

Posted: Mon Jul 09, 2007 5:32 pm
by Surfermondry
How will water, alchol, witchhazel, and hydrogen peroxiod absorb chromatography paper?

Re: Rf factors

Posted: Tue Jul 10, 2007 6:54 am
by Louise
Surfermondry wrote:How will water, alchol, witchhazel, and hydrogen peroxiod absorb chromatography paper?
The rf factor is determined by the interaction between the paper and the solvent. The solvent polarity and vapor pressure are important, as are specific interactions like hydrogen bonds. The paper can have different thickness/roughness/and chemical composition. If you do chromatography in a closed container vs. open container, you can get the solvent front moving at different rates. Hydrogen peroxide is almost never used as a solvent, since it "chews up" most compounds through vigourous redox reactions. Most chemists just test these factors each time they run a chromatogram.
Louise