Chromatography

[MercuryRising]

Explain how a polar solvent works in the seperation of polar dyes?
How might chromatography be useful in forensic science? i only thing i can think of is figuring out what pen the criminal used...
i really need help on this... :uhh:

[iansmith]

You could look at contaminant in the sample such as fibers. From the question, it probably chromatography in general rather than just seperating dyes.

As far as the role of polar solvant you should consider the physical properties of the dyes but this link might give you some insight.
http://www.google.ca/search?q=cache:HjOg5kAvEAkJ:www.chem.umn.edu/services/lecturedemo/info/column_chromatography.html+Chromatography+separati on+polar+dyes+polar+solvent&hl=en

[MercuryRising]

sorry...i did not get that...still clueless on how a polar solvent seperates polar dyes... :cry:

[chem_tr]

It lies on the interactions between adsorbent and solute; it is retarded by the adsorbent and since every solute has principally different interaction potential, you can theoretically separate the ingredients in a solute if you use a critical amount of needed polar solvent. However, in practice, it is not that easy. The polar the solvent is, the faster the solute go (if it is polar, too). If it is nonpolar, it starts to decelerate on the plate according to previous nonpolar runs. It may work, however, if your solute contains impurities which can be eluted under these circumstances.