TLC Jar/Plate

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Can someone explain if non polar or polar molecules travel farther? DAT Destroyer says non polar molecules travel the furthest, as polar molecules are attracted to the polar plate, but in my chad notes I have that polar molecule will travel the furthest... My subscription ran out so I can't confirm my notes. Thanks in advance!

Polar molecules travel the least because they are more attracted to plate. Non-polar molecules travel the furthest. I have that from destroyer and from Chad. I know at one point chad mentioned that if you have a really polar solvent it will out-compete the molecules and all molecules will travel further. Maybe that is what you have in your notes that is confusing you.

Originally Posted by n27s

Can someone explain if non polar or polar molecules travel farther? DAT Destroyer says non polar molecules travel the furthest, as polar molecules are attracted to the polar plate, but in my chad notes I have that polar molecule will travel the furthest... My subscription ran out so I can't confirm my notes. Thanks in advance!

you should go over Chad's video again I think you got your notes wrong

the TLC plate is made of silica/cellulose/aluminum oxide which is a polar plate
so polar molecules will be attracted more to the plate so it will move less along with the solvent

whereas the nonpolar molecules will be less attracted to the plate so will move more along with the solvent.

the polarity of the solvent affects also the distance that the analytes move
more polar the solvent is, the solvent will "disturb" the analyte molecules to be attracted to the plate so the analytes will move more than when the analytes are in the nonpolar solvents

so if your TLC result the Rf value is too big, than you just used too much polar solvent
and if your Rf value is too small then you just used too nonpolar solvent.

Originally Posted by mario0923

you should go over Chad's video again I think you got your notes wrong

the TLC plate is made of silica/cellulose/aluminum oxide which is a polar plate
so polar molecules will be attracted more to the plate so it will move less along with the solvent

whereas the nonpolar molecules will be less attracted to the plate so will move more along with the solvent.

the polarity of the solvent affects also the distance that the analytes move
more polar the solvent is, the solvent will "disturb" the analyte molecules to be attracted to the plate so the analytes will move more than when the analytes are in the nonpolar solvents

so if your TLC result the Rf value is too big, than you just used too much polar solvent
and if your Rf value is too small then you just used too nonpolar solvent.

i get it now, just re watched chad.

thanks y'all!