molar mass and TLC

[sv3]

Can the molar mass of a compound effect its Rf value on thin-layer chromatography?

So if you had two compunds that were pretty much identical but one had a slightly higher molar mass, could gravity play a role here in addition to polarity?

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[crazybob]

http://orgchem.colorado.edu/hndbksupport/TLC/TLCrf.html

 

[kentavr]

I would guess, that MM is a very minor factor for TLC. At least the precision of TLC may not be enough to separate that. I would argue that difference in MM compare to the phenomena that concentration of the solute in the column of solvent should be different with height. And this effect does exist if I remember correctly in the ocean where NaCl concentration depends on the depth, but it is pretty large column of water. In TLC they do not make such large size and capillary effect will not have enough force to operate with such huge height anyway.

 

[sv3]

http://orgchem.colorado.edu/hndbksupport/TLC/TLCrf.html

i read it thanks but don't know if answers my question. I understand what the Rf factor is but I'm wondering if the distance travelled up is affected by molar mass. I want to say no considering how small TLC appartus generally is but on a technical basis i'm wondering if it's yes.

 

[iheartmcats]

It would be unlikely that the MCAT would present a question regarding this. I would say to just concentrate on overall polarity as well as H-bonding ability of the molecule. I have never encountered a question that requires more than that.

 

[loveoforganic]

Agree with the above post. As a side note, I've never heard MM mentioned with TLC, so any effect it has is probably pretty minimal.

 

[sv3]

It would be unlikely that the MCAT would present a question regarding this. I would say to just concentrate on overall polarity as well as H-bonding ability of the molecule. I have never encountered a question that requires more than that.

it showed up on todays from what i read on another thread and i didnt know. hence me asking. But yeah since i never heard of the connection i woulda ignored it but it would have wasted time with forcing me to think of it